Breaking Down How All 255 First-Year Players Made Their MLB Debuts In 2024

Image credit: Jackson Chourio (Photo by Keith Gillett/Icon Sportswire via Getty Images)

After more than seven months, the 2024 MLB regular season is over.

From the opening games in Japan and stateside Opening Day to the playoff-settling doubleheader in Atlanta on Sept. 30, there have been ups and downs and twists and turns and plenty of plot lines to follow. Along the way, 255 players made their big league debuts. A trio of Padres—Jackson Merrill, Graham Pauley and Yuki Matsui— broke in on the first day possible (March 20) while Giants righthander Trevor McDonald did the same on the season’s final regularly scheduled day.

You can find the complete, 255-player list of 2024 debuts and signing scouts here.

Now, let’s take a look at the roads some of the players took to make their boyhood dreams come true.

Youngest Player

Brewers wunderkind Jackson Chourio was the youngest player to make his debut in 2024, and it wasn’t close. Milwaukee’s 20-year-old rookie sensation is the only current big leaguer to have been born in 2004, and he won’t turn 21 until Cactus League play in 2025.

Oldest Player

Righthander Brady Feigl pitched 273 innings in the minor leagues from 2014-2019 and pitched two stints apiece in the Atlantic League and the Dominican Winter League before making his MLB debut with Pittsburgh in August. Feigl was one of six players in their 30s to debut this season, joining Michael Petersen, Cam Booser, Tyler Ferguson, Naoyuki Uwasawa and Shota Imanaga.

Main Source

Of course, not every player who debuts does so for their original professional organization. The Giants, Athletics and White Sox helped 13 players apiece make their first big league appearances, but none of those three was the team where the most new big leaguers got their start. That honor went to the Yankees. While just five players made their debut in pinstripes, 18 players who got their start in the New York’s system saw their first big league action in 2024.

‘Bilt Different

The school with the most new big leaguers this year was Vanderbilt, which saw three first-rounders—Austin Martin, Jack Leiter and Kumar Rocker—plus lefty Jake Eder and righty Tyler Ferguson all get their first taste of the show. The Southeastern Conference also boasted the only other teams—Texas, LSU and Auburn—to land four new big leaguers in 2024.

Different Roads

There are several different avenues to the big leagues, some of which aren’t always well-paved. The main path to MLB this season was via the draft, with 110 of the 255 new big leaguers (around 43%) arriving this way. The next most common road to the show came through trade. Sixty-three previously traded said goodbye to one organization and, eventually, hello to the the big leagues.

Unsurprisingly, the White Sox, who spun off plenty of established big leaguers in recent years to help revamp their farm system, led the way in this category. Seven Chicago trade acquisitions made their debuts this season, including six pitchers. Second place in this category went to the Brewers, who acquired five big league pieces in trades. Their list is headed by righty Tobias Myers, whose 127 strikeouts were the 10th-most among all rookies.

Ten players selected in the Rule 5 Draft made their debuts, as did 29 free agents, seven players who were claimed on waivers and two undrafted free agents. Thirty-four of this year’s crop of new big leaguers entered pro ball as international free agents.

From Where?

As far as states are concerned, it should come as no surprise that California leads the way among the birthplaces of new big leaguers. The Golden State produced 30 players who made their debuts in 2024, followed—also unsurprisingly—by Florida (24) and Texas (18). Outside the U.S., 20 players from the Dominican Republic made their big league debuts, far and away the highest total among international players.