The case for each 2023 Rookie of the Year finalist

With each new season comes a fresh crop of young talent. Unsurprisingly, 2023's rookie class did not disappoint.

Among the finalists for 2023's AL and NL Rookie of the Year are a pair of dynamic, slick-fielding outfielders out of the NL West and two AL East infielders who, by season's end, were two of the biggest impact bats in baseball.

On the other side of the ball, we have a pitcher who will walk away with NL Cy Young Award votes and another who opened his season in Triple-A and ended it carrying his club's injury-depleted rotation on his back.

Here's a look at the case for each of the six finalists before the winners are announced Monday at 6 p.m. ET on MLB Network.

AMERICAN LEAGUE

Tanner Bibee, RHP, Guardians
There were a handful of rookie position players who had solid seasons this year, and Triston Casas and Gunnar Henderson were clearly at the top of that list. But when it comes to American League rookie pitchers, Bibee stood alone. Among AL rookies who tossed at least 100 innings, Bibee led in ERA (2.98), expected ERA (3.66), FIP (3.52), fWAR (3.0), innings pitched (142), left-on-base percentage (80%) and home runs per nine innings (0.82).

Bibee’s results shouldn’t just be compared to rookie hurlers. Of all Major League pitchers in 2023, the 24-year-old righty was one of just six to own a sub-3.00 ERA among those who threw at least 140 innings. His 0.82 homers-per-nine-innings ratio also ranked seventh best of those pitchers. The impact he made on the Guardians can’t be ignored, either. By the end of July, none of Cleveland’s Opening Day starters were in the rotation whether it be due to injuries or other roster moves. The rotation was left in the hands of rookies, and the 24-year-old Bibee stepped up to lead an inexperienced group to success.

Although Cleveland was eliminated from the postseason, Bibee’s efforts were a large reason why the team was still in contention through most of August. Without his hip injury at the end of the season, Bibee could’ve had a chance to pad his stats with two more opportunities to start, but the righty made the most of the 25 chances he had to toe the rubber in his rookie season.

-- Mandy Bell

Triston Casas, 1B, Red Sox
When Casas was hitting .128 on May 1, it was hard to believe what a strong case he would build for this award. But his in-season turnaround was something to behold.

From June 1 until his season ended on Sept. 14 due to a nagging right shoulder injury, Casas was as big a force as the Red Sox had in their lineup, putting together a line of .299/.397/.556 with 18 homers. The left-handed hitter had an eye-popping 1.034 OPS after the All-Star break.

Among qualified AL rookies with at least 400 at-bats, Casas finished first in OPS (.857), slugging percentage (.490) and on-base percentage (.367) while finishing second in homers (24) and walks (70) and fourth in RBIs (65).

Casas stood out not just among rookies, but among his more seasoned teammates, leading the club in walks, OBP and OPS while finishing second to Rafael Devers in homers.

Not only that, but Casas became the first qualified rookie for the Red Sox to lead the team in OPS since Fred Lynn in 1975. His OPS was the highest for a qualified Sox rookie since Nomar Garciaparra in 1997. Lynn and Garciaparra both won the Rookie of the Year in those seasons.

Perhaps the most impressive thing about Casas as a rookie was his advanced batting eye. According to Elias Sports Bureau, Casas is only the fourth Boston rookie to lead the club in walks. That small club includes Joe Foy (1966), Ted Williams (1939) and Marv Olson (1932).

Casas also has the advanced stats to back his case, as he ranked in MLB’s 75th percentile or higher in xwOBA (92nd, .371), walk rate (93rd, 13.9), xSLG (89th, .500), barrel rate (86th, 13.1), chase rate (86th, 22.1), hard-hit rate (80th, 46.6), and average exit velocity (77th, 91.1).

-- Ian Browne

Gunnar Henderson, 3B, Orioles
Henderson has already been named AL Rookie of the Year by both Sporting News and Baseball Digest. On Monday, the 22-year-old Orioles infielder should add the BBWAA honor to his growing list of accolades (which also now includes his first career Silver Slugger Award, won in the utility category).

The stats show why Henderson is widely considered the front-runner to receive this honor. He led all AL rookies in bWAR (6.2), fWAR (4.6), home runs (28), triples (nine), RBIs (82) and runs scored (100). Over 150 games, he slashed .255/.325/.489 and collected 66 extra-base hits.

Henderson put up those strong numbers despite a slow start to his first full big league season. After getting a 34-game taste of the Majors in 2022, his bat took some time to get going in ‘23, as he was hitting .170 at the end of play on May 12.

In June, though, Henderson was named AL Rookie of the Month. His bat heated up with the weather, as he slashed .320/.354/.640 with six homers and 16 RBIs in 20 games that month, showing why many pegged him as the AL Rookie of the Year favorite heading into 2023.

On defense, Henderson provided consistent exceptional play on the left side of the infield for Baltimore. He ranked third among AL shortstops with 10 defensive runs saved, despite making only 64 starts and playing 584 2/3 innings there. Henderson also had three DRS at third base, where he made 68 starts and logged 594 2/3 innings.

Not only should Henderson be named AL Rookie of the Year, but he should receive some down-ballot votes for AL MVP. His 6.2 bWAR led the 101-win American League East champion Orioles and ranked fifth in the AL.

-- Jake Rill

NATIONAL LEAGUE

Corbin Carroll, OF, D-backs
It’s hard to imagine anyone other than Carroll winning the NL Rookie of the Year Award. Not only has Carroll outperformed what the other finalists did from a statistical standpoint, he’s done things that no rookie has ever done before.

For instance, Carroll became the first rookie to hit 25 or more homers and steal 50 or more bases this year when he hit 25 and stole 54. If you’re looking for what he contributed to his team, he was the best player on a team that made it to the World Series, and there isn’t a player in a D-backs uniform who will try and tell you they would have been there without Carroll.

-- Steve Gilbert

James Outman, OF, Dodgers
Though Outman will have his work cut out for him to win the award, what the center fielder did this season should not be overlooked.

Coming into Spring Training, Outman was likely going to be on the outside looking in. But a season-ending injury to Gavin Lux opened the door for a left-handed bat on the roster. Outman outperformed just about everyone in camp and earned the Opening Day nod for the first time in his career.

Outman’s rookie season was a terrific development for the Dodgers. With a lot of uncertainty surrounding the middle of the defense with Cody Bellinger in Chicago, Outman stepped right in and performed beautifully. He played in 145 games this season, hitting 23 homers and driving in 70 runs.

In an offense that centered around Mookie Betts, Freddie Freeman and J.D. Martinez, Outman was able to complement them well toward the bottom of the lineup. But most important, it was Outman who carried the Dodgers in April, hitting six homers in the opening month, earning NL Rookie of the Month honors. Without Outman in the fold, the Dodgers’ slow start would’ve been even more concerning.

As impressive for Outman is that he was able to adjust back to the league after going through a two-month slump in the middle of the season. Outman had a .851 OPS in the second half of the season.

-- Juan Toribio

Kodai Senga, RHP, Mets
The case for Senga as National League Rookie of the Year begins and ends with a simple fact: no rookie starting pitcher was better.

Only six NL rookies started at least 20 games this season, and all but Senga finished with an ERA of 3.76 or higher. Senga’s 2.98 mark ranked second in the league among qualified pitchers of any experience level, making him the type of pitcher who figures to see his name on some Cy Young ballots, as well. There probably won’t be another NL rookie who can say that.

Senga’s problems only surface when voters start comparing him to Carroll, who accomplished something Senga could not by playing every day. For the same reason that starting pitchers do not frequently earn MVP votes, starters tend to lag behind their position-player counterparts in Rookie of the Year voting. To that end, Carroll’s production over 155 games is hard to deny.

But it’s not as if Senga barely pitched; to the contrary, he was the only rookie from either league to qualify for the ERA title. Among those first-year pitchers with even 100 innings, Senga led the pack in ERA, strikeouts and WAR and ranked fifth in WHIP. By season’s end, he was the Mets’ de facto ace.

By the way -- there’s precedent for a veteran Japanese pitcher to win Rookie of the Year, as Kazuhiro Sasaki did so for the Mariners in 2000 at age 32. Senga, at age 30, would be the oldest winner since that time.

-- Anthony DiComo