ST. LOUIS -- Two days after adding four Minor League prospects -- including three pitchers -- the Cardinals traded for three more promising young pitchers and a lefty-hitting infielder on Tuesday prior to the 5 p.m. CT Trade Deadline.

In dealing Jack Flaherty to Baltimore, St. Louis received infielder César Prieto and left-handers Drew Rom and Zack Showalter. Prieto and Rom will head to Triple-A Memphis, while Showalter will begin his Cardinals career with Single-A Palm Beach.

Earlier on Tuesday, St. Louis swapped veteran shortstop Paul DeJong for Minor League right-hander Matt Svanson. The 24-year-old Svanson, who grew up in Lake Zurich, Ill., was assigned to Double-A Springfield.   

Here is a closer look at the prospects that the Cardinals acquired on Tuesday:

INF César Prieto, Triple-A Memphis
Pipeline scouting report: Prieto established himself as a star in Cuba over four seasons in the Cuban National Series, where he claimed the league’s batting crown in 2021. He was in the midst of a league-record 44-game hit streak when he defected in May 2021, settling in Tampa, Fla., before the Orioles signed him for $650,000 as part of their 2020-21 international class. Prieto made an impact right away at High-A Aberdeen as a 23-year-old, batting .340 with a 1.000 OPS to earn a promotion to Double-A after only 25 games. But his contact-heavy approach wasn’t effective in Bowie, where he hit only .255/.296/.348 with a 58-15 strikeout-to-walk rate in 90 games. Prieto amassed a .364 average in his return to Double-A this season and had a .317/.365/.471 line in 27 Triple-A games before he was traded to the Cardinals at the Deadline for Jack Flaherty.

Prieto’s bat-to-ball skills drew comparisons to Cubs second baseman Nick Madrigal coming out of Cuba, when he was considered an excellent contact hitter with questionable power from the left side of the plate. But that profile flipped somewhat stateside. Prieto instead showed surprising power, socking 11 homers in his first 115 Minor League games, while his contact rate and plate discipline didn’t translate as expected. On the bases, he’s a solid-to-average runner with good baseball acumen and fundamentals.

Signed as a second baseman, Prieto predominately played third at Bowie and exclusively at the hot corner in the Fall League. He also got his feet wet at short for the Baysox during the regular season and continued to play all three spots in 2023. He profiles as an average defender at both second and third who is athletic enough to play short in a pinch, with the ceiling of a useful utilityman who can provide some left-handed punch off the bench at the highest level.

Organizational fit: The 24-year-old Prieto is in just his second season of professional baseball after signing with the Orioles out of Cuba in 2022. He is already ranked as the No. 9 prospect in the Cardinals' system, per MLB Pipeline. Much like Cards utility ace Brendan Donovan, the left-handed-hitting Prieto has played second base, shortstop and third base already in the Minor Leagues. The 5-foot-9, 175-pounder hit .349 with an .868 OPS at Double-A Bowie and Triple-A Norfolk this season in 85 games. His versatility will be highly coveted by a Cardinals franchise that wants to shore up its defense in 2024 following some slippage in '23.

ETA: 2024

LHP Drew Rom, Triple-A Memphis
Pipeline scouting report: Rom rose steadily through Baltimore's system after the O’s plucked him out of the Kentucky prep ranks in the fourth round of the 2018 MLB Draft, signing him for an above-slot $650,000 bonus. The tall, lanky lefty did little but produce at the lower levels, reaching Double-A Bowie in ’21 as a 21-year-old and Triple-A last summer at age 22. The Orioles added him to their 40-man roster in November, hinting at an imminent debut, but that didn’t come early in 2023 and he was traded to the Cardinals at the Trade Deadline in a deal involving Jack Flaherty.

Rom relies on deception more than elite stuff, using his 6-foot-2 frame to hide the ball well and a three-quarters arm slot, long stride and crossfire finish to create good extension. Rom’s arm action is quick and tough to time, and the extension he generates enables his stuff to play up and miss barrels with regularity. He works predominantly off a high-spin fastball that’s ticked up in recent years and can now reach the low 90s, with a flat angle that makes it difficult for hitters to get on top of. He throws a potential plus slurve with varying shapes in the low 80s, commanding it to both sides of the plate, and also features an intriguing split-change. A former high school soccer player, Rom also earns high marks for his athleticism and makeup, as well as a moderate-effort delivery that projects durability.

Rom excelled at the lower levels thanks to outstanding control, but that wavered along with his results last summer at both Double-A and Triple-A. While he kept his strikeout rate high at the upper levels, his walks increased and his ground-ball rate dropped -- somewhat concerning for a pitcher who thrives on pitchability more than overpowering stuff. In short, Rom’s ceiling looks as high as his command will take it. That continued to take a step back in 2023, and he might end up being more of a swingman in the Majors than a true starter unless he can find better command in the St. Louis system.

Organizational fit: Rom, 23, will provide some of the swing-and-miss that the Cardinals covet, and it’s even a greater benefit that he does it from the left side. After stocking their staff with strike-throwing hurlers who pitched to contact and depended on the defense and positioning in shifts, the Cardinals want to find more pitchers going forward who miss bats. Rom does just that, striking out 100 batters in 86 innings this season at Triple-A Norfolk. MLB Pipeline has him ranked as the No. 26 prospect in the Cards' system.

ETA: 2024

LHP Zack Showalter, Class-A Palm Beach
Pipeline scouting report: Coming out of Wesley Chapel (Fla.) High School just north of Tampa, Showalter looked like he was a decent bet to honor his commitment to the University of South Florida as his name kept dropping in the 2022 MLB Draft. The Orioles swooped in during the 11th round -- when bonus slots were no longer an issue -- and signed him for $440,000 -- $315,000 of which counted toward their pool. The 19-year-old right-hander was off to a promising start in 2023, pitching his way out of the Florida Complex League (where he struck out 16 in 10 innings) and into Single-A ball when the Cardinals acquired him at the Trade Deadline for Jack Flaherty.

The 6-foot-2 right-hander hides the ball well in his delivery before firing in a fastball that touches the mid-90s. The ball rides well up in the zone and comes in almost flat, giving an almost explosive look, and those characteristics have helped drive his early success in the lower levels of the Minors. Showalter also shows the makings of an average slider that keeps hitters honest, and he’ll need to improve his changeup in order to perform better against lefties, who had a .933 OPS against him before the trade (compared to only .525 for righties).

Showalter’s control is an early issue, and leading up to the Draft, some scouts believed the effort in his delivery would eventually send him to the bullpen. That could still happen, but he should get a long look at starting in the St. Louis system.

Organizational fit: The 19-year-old Showalter is likely years away from reaching the big leagues, but MLB Pipeline already has him ranked as the No. 23 prospect in the Cardinals' system because of his stellar arm talent. In his first year of pro ball, the 13th-round pick from the 2022 MLB Draft has a 32 percent strikeout rate and a 46 percent ground-ball rate over nine games (eight starts). He’ll head to Single-A Palm Beach where the Cardinals hope his maturing body and solid mechanics will allow him to progress quickly through the organization’s Minor League system.

ERA: 2026

RHP Matt Svanson, Double-A Springfield
Pipeline scouting report: The 6-foot-5, 235-pound Svanson should fit right in with a Cardinals organization that has traditionally liked tall, hard-throwing right-handers who get ground balls at a high right. Svanson, a native of Lake Zurich, Ill., has a strong history of pitching at a high level. He threw two perfect games and two other no-hitters during his prep days at Lake Zurich High School. And earlier this season, Svanson was a part of a combined no-hitter for High-A Vancouver. Svanson, 24, pitched for Lehigh University before becoming a 13-round pick of the 2021 MLB Draft.

Organizational fit: This season, Svanson went 4-1 with a 1.11 ERA in 26 relief appearances between stops with Single-A Dunedin and High-A Vancouver. For a Cardinals franchise in search of more swing-and-missfrom itspitchers, Svanson projects as someone who could miss more bats in the future.

ETA: 2025

RHP Tekoah Roby, Cardinals Complex in Jupiter, Fla.
Pipeline scouting report: After taking Evan Carter in the second round of the 2020 Draft, the Rangers used their third-round pick on another high schooler whom they valued more than the rest of the industry. They signed Roby away from a commitment to Troy for a slightly over-slot $775,000 and have been pleased by his development since. After getting shut down with a sprained elbow in 2021, he was fully healthy last year and held his own as one of the youngest starters (age 20) in the High-A South Atlantic League. Roby moved up to Double-A Frisco and was better than his traditional numbers in 2023, when he was moved to St. Louis in the Jordan Montgomery deal while he nursed a shoulder injury.

Roby can attack in any direction with his four-pitch repertoire. He can work north and south by pairing a fastball that plays better than its 92-96 mph velocity thanks to its outstanding induced vertical break and the extension in his delivery with a high-spin upper-70s curveball with downer break. He can also operate east and west with a fading low-80s changeup moving in the opposite direction from a low-80s slider that he added last summer.

Though Roby may not have a true plus pitch, he could have four solid offerings once he's fully developed. He has a loose arm and repeats his delivery well enough to provide strikes, though his command is a work in progress. He misses in the middle of the zone more than he should, leaving him vulnerable to homers, but he could become a mid-rotation starter if he locates his pitches more consistently as he gains experience.

Organizational fit: To fully illustrate how barren the Cardinals' farm system is of elite pitching talent, consider this: Whereas Roby was the No. 11-ranked prospect in the Rangers' system, he was immediately slotted in at No. 4 in the Cardinals' system following the trade, per MLB Pipeline. Roby, who has been out since June 6 with a shoulder injury, will report to the Cardinals' complex in Jupiter, Fla., where he will be fully evaluated. After viewing his medical evaluations, the Cardinals are confident that the 21-year-old from Pensacola, Fla., will pitch again this season -- and their hopes are that he will do so at Triple-A Memphis to potentially ready him for the big leagues in 2024

ETA: 2024

INF Thomas Saggese, Triple-A Memphis
Pipeline scouting report: The Rangers used their last four selections in the shortened five-round 2020 Draft on prepsters whom they rated higher than the industry consensus, and the early returns are good on Evan Carter (second round), Tekoah Roby (third) and Saggese (fifth). They used an over-slot $800,000 bonus to divert Saggese from his Pepperdine commitment because they liked his bat, which has lived up to their expectations. He batted .308 in High-A last season, missing out on the South Atlantic League batting crown title by one hit, then went 13-for-36 (.361) in Double-A to help Frisco win the Texas League championship. Saggese returned to the Texas League with a strong showing before getting moved to St. Louis at the Trade Deadline in a deal for Jordan Montgomery.

A right-handed hitter with a handsy stroke and aggressive approach, Saggese looks to drive the ball in the air to his pull side. He should have 20-homer power once he adds more strength, and he could become a solid hitter if he can develop more discipline. He flashes some aptitude for recognizing pitches and working counts but likes to turn his swing loose.

Saggese saw time at all four infield positions in 2022, getting most of his action at second and third base. As a decent athlete with fringy speed and average arm strength, he's best suited for second, where he's a sure-handed defender. He draws praise for his makeup and won Texas’ True Ranger Award last year for representing its core values on and off the field.

Organizational fit: The Cardinals already have two defensive aces in Gold Glovers Tommy Edman and Brendan Donovan, but they pushed for the inclusion of Saggese because, as team president John Mozeliak said, “he’s just a baseball player.” Saggese’s production in Double-A as a 21-year-old prospect (slashing .314/.380/.514 with a 133 wRC+) is very similar to what prized rookie Jordan Walker did at Double-A as a 20-year-old prospect (slashing .306/.388/.510 with a 128 wRC+).

ETA: 2024

RHP Sem Robberse, Triple-A Memphis
Pipeline scouting report: Robberse is a unique development story, originally signed out of Zeist, Netherlands, in 2019. He was able to make his pro debut in the Rookie-level Gulf Coast League that season, allowing just one run over 10 1/3 innings. When the pandemic stopped baseball, Robberse was unable to return to the Netherlands and stayed at a hotel near the Blue Jays’ complex with a group of prospects, including many of the Venezuelan players. This added yet another interesting wrinkle to his growth as he was often forced to work out by himself.

Coming out of that, Robberse posted a 4.36 ERA over 88 2/3 innings in 2021, split between Single-A Dunedin and High-A Vancouver. Each number moved in the right direction in 2022, as Robberse climbed another level to Double-A and finished with a cumulative ERA of 3.23 over 111 1/3 innings, striking out 97. Much of Robberse’s game is self-taught, which gives him a unique ability to adjust on the fly, and the Blue Jays were encouraged with some of his physical growth, too.

After trying to keep on weight for years, Robberse finally packed it on in ’22 and is now up above 200 pounds, which was the goal. There’s hope this can bump his fastball up closer to the 93-94 mph range eventually. An increased strikeout ability would serve Robberse well, as at this point he relies on finesse with a promising package of secondaries. Now with the Cardinals after a Jordan Hicks trade at the 2023 Deadline, the Futures Game participant can carry his momentum forward in hopes of joining a future St. Louis rotation.

Organizational fit: The Cardinals are excited about getting Robberse to Triple-A at 21 years old, but he is still very much an unfinished product and will need to make major strides to be big league ready by next season for a club that has plans on contending in 2023. The St. Louis brass is excited that Robberse has a nice mix of swing-and-miss and a high ground ball rate -- two assets that will be welcome on a staff that has largely pitched to contact and depended on the defense in recent years.

ETA: 2024

RHP Adam Kloffenstein, Triple-A Memphis
Pipeline scouting report: The Blue Jays made headlines when they selected good friends and Texas high school teammates Jordan Groshans and Kloffenstein in the first and third rounds of the 2018 Draft, respectively. For Kloffenstein, it’s been an up-and-down time in pro ball over the five years since that day. He's been on the upswing now, however, with a repeat of Double-A New Hampshire, where he dropped his ERA nearly three runs from his 6.07 mark last season. The Cardinals acquired him in a deal for Jordan Hicks at the 2023 Trade Deadline.

Standing tall on the mound at 6-foot-5, Kloffenstein runs a low-90s sinker in on righties that helps him limit damage against same-side bats and generate groundball rates around 50 percent, and he can run a four-seamer up to 96. He can work with both a mid-80s sweeper and an upper-80s cutter -- the latter of which came as a result of constant tinkering that led him to utilize a pitch with shorter action. It plays well off the two-seam and has helped fuel Kloffenstein’s rise in K’s. He’ll show the makings of a curveball and changeup too, but the righty is often at his best when he’s working east-west.

Kloffenstein’s walk rate has similarly improved as he’s grown more confident in his stuff. Even during the dips in his rollercoaster career, the former TCU commit previously impressed Toronto brass by staying healthy and regularly taking his spots in the rotation. Now with sharper stuff and still young in his age-22 season, his chances at being a backend Major League starter are his best in years. 

Organizational fit: The Cardinals love their tall, hard-throwing right-handers (see: Adam Wainwright, Jack Flaherty, Drew VerHagen and Chris Stratton to name a few), and the 6-foot-5, 243-pound Kloffenstein should fit right in. The Cardinals were especially impressed with the progress he made this past season while lowering his ERA to 3.24 (sixth-best in Double-A) over 17 starts. He’ll get an immediate shot to test out that growth at the Triple-A level in Memphis.

ETA: 2024