Tuesday was a busy day for all 30 teams in terms of roster maintenance.

With a deadline at 6 p.m. ET to make decisions on who to add to 40-man rosters, the transaction wire was firing away and a large number of prospects were added to protect them from being taken in December’s Rule 5 Draft.

Players first signed at age 18 or younger must be added to 40-man rosters within five seasons or they become eligible to be drafted by other organizations through the Rule 5 process. Players signed at 19 years or older have to be protected within four seasons. Clubs pay $100,000 to select a player in the Major League phase of the Rule 5 Draft. If that player doesn't stay on the big league active roster for the full season, he must be offered back to his former team for $50,000.

For this year, that means an international or high school Draft pick signed in 2018 had to be protected. A college player taken in the 2019 Draft was in the same position. There were 15 players on MLB Pipeline’s Top 100 who needed to be protected, led by No. 4 overall Grayson Rodriguez of the Orioles, and not surprisingly, all 15 were added to rosters. A total of 76 prospects on Top 30 lists also earned roster spots.

But there were also a good number of unranked prospects who were protected on Tuesday, and they’re definitely worth keeping an eye on. Last year’s list of intriguing unranked prospects included the Guardians’ Steven Kwan, who finished third in this year’s American League Rookie of the Year voting, and Orioles reliever Félix Bautista, who ended up being Baltimore’s closer.

Here are 10 players who were unranked at the time of being protected this year who hope they can follow that path in 2023:

Jake Alu, INF, Nationals: A 24th-round pick in 2019 out of Boston College, Alu has shown a knack for making contact from the left side of the plate. He hit .323/.372/.553 in Triple-A last year and showed off a bit more pop overall with 40 doubles and 20 homers combined between Double-A and Triple-A while not striking out much. He played mostly third base and saw time at second and left field, but it’s his bat that should get him to the big leagues at age 26 next season.

Isaiah Campbell, RHP, Mariners: Campbell was added to the Mariners’ Top 30 on Wednesday when the Teoscar Hernández trade sent Adam Macko to the Blue Jays. The 2019 second-rounder out of Arkansas has raised his profile with a full-time move to the bullpen after having trouble staying healthy in 2021 and now features a fastball that sits at 96 mph and a nasty sweeping slider.

Jonny DeLuca, OF, Dodgers: The Dodgers took DeLuca in Round 25 of the 2019 Draft and have watched him make some very impressive strides in turning his athleticism into performance. He had been a track standout in high school before focusing on baseball at Oregon and is still an explosive athlete with some loud tools. He has an intriguing power-speed combination, and his improvements in terms of plate discipline have helped him use those tools, as he finished 2022 with 25 homers and 17 steals.

Brent Headrick, LHP, Twins: A 2019 ninth-rounder out of Illinois State, Headrick reached Double-A for the first time and really came on as the 2022 season wore on. He’s a 6-foot-6 lefty whose stuff ticked upwards this past season, with a fastball that went from around 89 mph in 2021 to averaging just shy of 92 mph this past year to go along with a harder slider that featured more depth. There could be more to come here and he has the chance to start, though that stuff could be nasty from the left side in a bullpen and he could have been a Rule 5 hot commodity as a result.

Matt Krook, LHP, Yankees: Krook was a supplemental first-round pick out of high school way back in 2013, didn’t sign, went to Oregon and was a fourth-rounder of the Giants in 2016. Traded to the Rays in the Dec. 2017 Evan Longoria deal, he was really held back by injuries, and the Yankees nabbed him in the Minor League phase of the 2020 Rule 5 Draft. He’s now 28 and on a roster for the first time as a lefty who gets a ton of groundball outs (1.80 GO/AO last year) and misses bats with his slider and changeup.

Roddery Munoz, RHP, Braves: Signed for just $30,000 in June 2018, Munoz has worked mostly as a starter in the Braves' system, though he missed a chunk of the 2021 season with injury. He struck out 10.7 per nine in 2022 and reached Double-A while topping 100 IP for the first time. He could end up in a bullpen, and with a 95-98 mph fastball and a slider that flashes plus, he’d be the kind of power arm to whom teams would give a long Rule 5 look.

Riley Pint, RHP, Rockies: This could be a terrific comeback story. Pint was the No. 4 overall pick in the 2016 Draft, but a combination of injuries and an inability to throw strikes led to him leaving the game completely. But he came back in 2022 and reached Triple-A as a reliever. Command is still an issue, but he struck out 11.4 per nine this past season with a fastball that easily touches the upper-90s and a nasty slider to complement it.

Sean Reynolds, RHP, Marlins: Reynolds was a fourth-round pick out of high school in 2016… as an outfielder/first baseman. He had tremendous raw power but couldn’t make enough contact to get to it, so he moved to the mound in 2021. He pitched his way to Double-A this past year, striking out 11.4 per nine and holding hitters to a .201 batting average. The 6-foot-8 right-hander threw his fastball in the 97-100 mph range in 2022.

Jon Singleton, 1B, Brewers: True, he’s not a prospect anymore, but this is quite a redemption story in the making. Singleton was once a top-level prospect, one who seemed like the future at first base for the Astros. But he hasn’t been in the big leagues since 2015, was out of baseball from 2018 through 2020 and played in Mexico in 2021 before finishing second in the Brewers' system with 24 homers and leading all of the Minor Leagues with 117 walks in 2022. He signed a Minor League deal with the Brewers last month, leaving him exposed for Rule 5 consideration, so the Brewers added the 31-year-old, marking the first time he’s been on a 40-man since Nov. 2016.

Colby White, RHP, Rays: The Mississippi State product was the Rays’ sixth-round pick in 2019. He’s been on their Top 30 in the past and after a 2021 season that saw him pitch his way to Triple-A, he looked like he might impact the big league 'pen in 2022 until he needed Tommy John surgery in April. Assuming a return to health in 2023, he should be able to bring his 95-97 mph fastball, which he locates well up in the zone, along with a very effective slider, to Tampa.