The Best ‘Redshirt Rookie’ Seasons in MLB Since 2010 

To address a question many of you may be asking, “What is a ‘redshirt rookie season’?”

Coined by JustBaseball’s editor-in-chief Ryan Finkelstein, it is basically when a player gets called up and finishes that season with his rookie eligibility still intact for the following year.

Because, as you know, a player’s rookie year isn’t the year they debut in, it is the season they exceed the rookie limits in.

And for context, the rookie limits are based on the following qualifiers:

• 130 At-Bats
• 50 Innings Pitched
• 45 days on the active roster

Since the adoption of the Prospect Promotion Incentives (PPI), teams have become even more intentional in preserving rookie status on their top prospects, as doing so could result in being awarded invaluable future draft capital.

This past season, the New York Mets waited until August 16th for top prospect Nolan McLean to make his MLB debut. Had he debuted a day earlier, McLean would have reached 45 days of service time by the end of the season.

Instead, he finished the season exactly one day short of exceeding his rookie limits and two innings shy of reaching the 50-inning threshold as well. McLean was just ranked as the top pitching prospect in baseball in our latest top 100, and he is the early favorite to win the 2026 NL Rookie of the Year.

All of this hype stems from a remarkable redshirt rookie campaign, where McLean stepped up and became an instant ace for the Mets, doing everything he could to keep their season alive, going 5-1 and pitching to a 2.06 ERA in eight starts down the stretch.

McLean wasn’t the only redshirt rookie to thrive in 2025, though, as Trey Yesavage took center stage once we got into October. Let’s go back over the past 15 years, and break down some of the best redshirt rookie seasons we have enjoyed.

2013: Billy Hamilton, Cincinnati Reds

Billy Hamilton stole 155 bases in 132 minor league games in 2012. 

I don’t need to expand further; people were excited about his MLB debut because his speed was game-changing. And when he got the call-up in September 2013, it was on full display.

Before even taking a plate appearance, he was four-for-four on steal attempts as a pinch runner. 

And in his first start on September 18th versus Houston, Hamilton reached base five times and stole four more bags in a 13-inning victory.

In the end, he hit .368 with 13 stolen bases and a 0.7 bWAR in only 13 games.

Although Hamilton didn’t quite hit enough to have a truly productive big-league career, the speed helped him have some solid seasons.

2015: Corey Seager, Los Angeles Dodgers

At 21 years old, Corey Seager laid the groundwork for his incredible MLB career. 

The 2012 first-round pick made his big league debut in September 2015 and quickly ripped away the starting job from Jimmy Rollins due to a .337 AVG, a .986 OPS, and 13 extra base hits in less than 100 at-bats. He reached base safely in 24 of his 25 starts and had an absurd 1.7 bWAR/1.5 fWAR in just 27 games. 

He wasn’t quite a factor in the playoffs that year, but he parlayed this appetizer of greatness into a 2016 season where he won the Rookie of the Year award and finished third in MVP voting.

2016: Dansby Swanson, Atlanta Braves

The 2015 MLB draft’s first overall pick, Dansby Swanson, was so good he couldn’t even get through his first minor league season in 2016 without getting the call to the big leagues. 

The flashy shortstop put his potential on full display in his 38 games with Atlanta.

Pushing his redshirt status to the brink while hitting .302 with an .803 OPS, and a win of WAR. Redshirt Dansby was just exciting. His first career homer was an inside-the-parker versus Washington, and his defensive tape was insane. 

Swanson’s career has blossomed into a very successful one, and while it took a few years for the bat to come back around again, he is consistently one of the more valuable players at the position.

2018: Willians Astudillo, Minnesota Twins

Now it is time for a slightly deeper pull.

Willians Astudiilio, or La Tortuga, bounced around several pro organizations from 2008 to 2017.

But in 2018, he finally got his big league shot for the Twins over 30 games at six positions, including an inning on the mound.

However, the catcher/third baseman did not let his opportunity pass him by, hitting .355 with three homers and only three strikeouts over 93 at-bats.

He never recaptured this success, but it was nice to see someone who had such a long grind of a career have his moment.

2020: Ian Anderson, Atlanta Braves

The 2020 cardboard cutout season was kind of a difficult year to measure, as its shortened nature allowed a lot of guys to escape with their rookie status intact, but three were hard to ignore.

Ian Anderson, the third overall pick in 2016, debuted for the Braves in late August 2020. And not only did he pitch to a sub-2 ERA over six starts down the stretch, but he also got through his first three postseason starts scoreless.

Anderson finished seventh in Rookie of the Year voting despite still having his status, and this allowed him to finish fifth in voting the following year while pitching wonderfully on the road to a World Series. 

His career since however, has been plagued by injury and poor performance.

2020: Randy Arozarena, Tampa Bay Rays

Randy Arozarena had perhaps the greatest postseason run of all time before winning the Rookie of the Year award in 2021. 

Arozarena debuted in 2019 for the Cardinals and actually played in that year’s playoffs.

But things got crazy after he was traded to Tampa Bay. Because Randy, following a 1.000+ OPS in the final few weeks of 2020, ripped off a 1.273 OPS with a record-setting 10 home runs in the playoffs in a runner-up championship finish to the Dodgers. 

While Arozarena did not keep up that historic pace, he has put up good seasons every year after.

2020: Ke’Bryan Hayes, Pittsburgh Pirates

“What if Ke’Bryan Hayes was a league-average hitter?”

That has been the question on the minds of many baseball fans over the last few years, as Hayes’ glove is so ridiculous that if he could just be competent with the bat, he would be a star. 

In 2020, however, he wasn’t just average; he was double the average. 

You see, in just 24 games in the final month of the 2020 season, Hayes had a .376 AVG, five home runs, and a 1.124 OPS, good for a 201 OPS+, which is 101% above average. 

This allowed Hayes to post a 1.9 WAR according to both major measurements, and according to my research, that is the highest WAR a hitter has ever posted while keeping their AL/NL rookie status intact. 

2021: Tyler Gilbert, Arizona Diamondbacks

This run had one of the most memorable starts of recent memory.

Tyler Gilbert had pitched in 163 minor league games, mostly as a reliever, prior to his MLB debut out of the bullpen for the D-Backs in August 2021. 

But with starter Caleb Smith struggling, the Snakes decided to give Gilbert the ball for his first career start on August 14th, and well, he just casually threw a no-hitter against the Padres. 

Gilbert finished 2021 with a 3.15 ERA over 40 innings. While his first few seasons after were not great, he just wrapped up a pretty solid season out of the bullpen for the White Sox.  

2022: Corbin Carroll, Arizona Diamondbacks

Staying with the Diamondbacks, this cameo got this guy paid. 

Corbin Carroll, a highly regarded prospect, came up at the end of August in 2022 and hit the ground running. He banged nine doubles, launched four homers, and rocked an .832 OPS over 32 games to post a WAR a shade under 1.5.

This gave Arizona the confidence to hand him an eight-year, $111 million extension before the 2023 season. A year in which the team won the National League pennant, and Carroll won the Rookie of the Year award.

2023: Evan Carter, Texas Rangers

This might be the best September call-up ever. 

If you only looked at the regular season, Carter still would make this list, as he had a 1.058 OPS over 23 games, and his approach was so good given the nickname “Full Count Carter”.

But the postseason brought this run from great to historic. 

In the 2023 playoffs, Evan Carter hit .300 with a playoff record nine doubles. He drew nine walks and was so poised in the box that the 21-year-old was batting third for an eventual championship-winning team before his rookie eligibility ran out. 

Nagging injuries have prevented Carter from building upon this, but he is still only 23 years old. 

2024: Rhett Lowder, Cincinnati Reds

The story of the 2024 season, when it came to rookie pitchers, was without a doubt Paul Skenes. He won the Rookie of the Year award and finished third in Cy Young voting.

But his dance partner in one of the greatest pitching duels ever in the 2023 College Baseball World Series, Rhett Lowder, also put on a show. 

In six MLB starts in 2024, Lowder allowed one run or less five times, surrendered zero home runs, and finished the fifth inning all but one time. 

This led to an incredible 1.17 ERA, a mark close to the best six-start stretch of Skenes’ career by ERA that was happening almost simultaneously. However, despite not pitching in MLB this past season due to injuries, he was on the active roster for long enough to lose his rookie status for 2026.

2025: Nolan McLean, New York Mets

From his first inning in the show, you knew Nolan McLean was going to be a problem.

Nolan McLean didn’t start focusing on pitching full-time until this year, as the Mets let him explore being a two-way player in the minor leagues to varying success. 

But, being locked into pitching led to a major leap in 2025, and following torching the minor leagues, McLean made his MLB debut on August 16th. 

His whiffleball-type stuff quickly baffled MLB hitters and helped him make eight starts at a 2.06 ERA while striking out almost 11 hitters per nine. McLean received some down-ballot Rookie of the Year votes, but figures to be a more prominent figure in the race next year.

If it wasn’t for McLean, the Mets’ collapse would have come faster. His ability to pitch effectively and deep into games was something they desperately needed after the first two months of 2025, and it came from a 24-year-old prospect. 

As it stands, McLean is entering 2025 as the Mets’ ace, and I am very curious to see how his actual rookie season goes.

2025: Trey Yesavage, Toronto Blue Jays

Trey Yesavage’s 2025 was one of the wildest years for a ballplayer ever.

Yesavage, a 2024 first-round pick, started 2025 in A-ball in front of a few hundred people, but he ended it in Game 7 of the World Series. 

After working his way through four minor league levels, Yesavage and his bizarre, sky-high release point touched down in MLB on September 15th. 

But, Yesavage didn’t really start making a name for himself until the calendar flipped to October.

His first playoff start came in ALDS Game 2 in Toronto versus the Yankees. Where MLB’s best offense in the regular season was so puzzled by the 22-year-old’s unique release point and disappearing splitter, that they mustered up zero hits through 5 1/3 innings and struck out 11 times.

And while his three postseason starts after were hit-or-miss. In Game 5 of the World Series, versus the mighty Dodgers, Yesavage struck out 12 over seven innings of one-run ball to put his Blue Jays a win away from a championship. 

However, Los Angeles rallied off the mat to win in seven, with that final game seeing Yesavage, on two days’ rest, allow a homer to Max Muncy in the eighth inning. 

Regardless, having a postseason run like this before your official rookie season is insane.