The last player to appear in a major league game before his 19th birthday was Alex Rodriguez. A-Rod debuted for the Mariners on July 8, 1994, 19 days before turning 19. Since then, just a handful of 19 year-olds have appeared, including such notables as Andruw Jones, Edgar Renteria, Adrian Beltre and Felix Hernandez. The Upton brothers, Justin and B.J., also both debuted just prior to turning 20 (does anyone know if any other brothers have debuted as teenagers?)

But, teenagers weren’t always so scarce. During World War II, and in the bonus baby days of the 1950s and 1960s, there was a relative abundance of teenagers in the majors, with some teams sporting several on their rosters. And, it wasn’t just 19 year-olds – Joe Nuxhall famously debuted as a 15 year-old and a number of 16, 17 and 18 year-old players have also had major league playing time.

With that preamble, I’m following up an earlier post on the oldest batter vs. pitcher matchups with this post, highlighting the youngest such matchups.

The youngest batter vs. pitcher matchups I can find in the game-searchable era are these ones, with both batter and pitcher under 19 years of age. The chronological list shows the first matchup for each pair, with the youngest matchup in the list in bold face type. You can click the game and player links for more information.

The 1936 Feller/Gumpert matchup was Feller’s famous 17 strikeout game. Both pitchers also pitched complete games in that tilt, obviously the youngest pair of pitchers to accomplish that feat. Feller, of course, would become an all-time great, while Gumpert went on to a respectable journeyman career that included one all-star game appearance.

The youngest ever matchup was Cass Michaels and Carl Scheib in 1944, although both had debuted the prior season, Scheib doing so at age 16. In 1945, Michaels would be the White Sox regular SS at age 19. Both would go on to journeyman careers lasting until 1954.

In the 1957 game, Mike McCormick got the win in 8.2 innings of relief of starter Stu Miller who allowed 2 HR, a walk and a hit batsman in his first 5 batters. The batting matchup shown here occurred in the 7^th inning, after the Cardinals’ Bob Miller relieved Hoyt Wilhelm. Both players would pitch into the early 1970s, with McCormick getting two All-Star nods, plus the 1967 NL Cy Young award.

To fill out this list, I’ve found batter-pitcher combinations where combined age was under 38 years. Here are those games, chronologically.

Somewhat surprisingly, only one 1944 Brooklyn Dodger appears. That team featured no fewer than 8 teenagers, 4 pitchers and 4 position players. Plus, they had two other 20 year-old pitchers. Tommy Brown debuted as a 16 year-old in early August 1944, ten days later becoming the Dodgers regular shortstop for the remainder of the season, the youngest ever to play regularly in the majors. Brown played in 9 seasons but was limited by his career .916 fielding % as a shortstop (league average for SS at the time was .953).

Andy Hansen, who was matched up with both Tommy Brown and Granny Hamner, would stick with the Giants for 6 seasons before joining Hamner in Philadelphia, where Hamner earned All-Star selections in 3 successive seasons in the early 1950s. Hamner also had an older brother, Garvin, with the two brothers, aged 17 and 21, forming the Phillies starting middle infield on opening day 1945, and through the first month of that season.

The Tigers debuted two teenage pitchers in 1945. Billy Pierce would go on to become a 7-time all-star, winning over 200 games in an 18-year career that included World Series appearances for the White Sox and Giants. Houtteman would pitch for 12 seasons, garnering one all-star selection.

The 1953 game was Joey Jay’s career debut.  Two months later, Jay would become the youngest pitcher to hurl a shutout, albeit a rain-shortened 7-inning one. Jay would go on to back-to-back twenty win seasons for Cincinnati, leading the Reds to the 1961 NL pennant with league-leading totals of 21 wins and 4 shutouts. The Phillies would stick with Kazanski for 6 seasons, long enough for him to crack the top 20 in lowest career OPS+ for non-pitchers (min. 1400 PAs). Among players with careers of that length for just one franchise, Kazanski jumps to 2nd lowest career OPS+, ahead of only Jim Levey, a shortstop for the 1930s Browns.

The Klimchock/McIlwain matchup was the second career game for both players, and the career finale for McIlwain. Klimchock would go on for 12 seasons as a utility player, only once exceeding 130 PA.

Ed Kranepool was one of the most precocious players ever, trailing only Phil Cavarretta and Mel Ott in games played up to the age 18 season. Zachary would have an undistinguished career in limited duty for 9 seasons. He is among the top 20 all-time in lowest W-L% and lowest ERA+ for a career (min. 100 games).

Highly-touted David Clyde took the loss in this 1974 game, evening his record at 3-3 after starting the season 3-0 on 3 impressive complete game triumphs. He didn’t know it then, but Clyde would not earn another W until 4 years later when he again got off to a fast 4-0 start before fading to an 8-11 mark for the 1978 season. A year after that, his career was over. Yount, of course, would fare rather better, joining Feller from the first list in the HOF.

To finish off the batter-pitcher matchups, here are the youngest to appear in the post-season and All-Star Game.

Most everyone is familiar with Joe Nuxhall‘s pitching debut at age 15. Here are some other precocious accomplishments that may be less well known:

Youngest to appear in various opening day roles:

Youngest to appear in various post-season roles:

Note that Andruw Jones’ 1996 post-season included home runs in 3 consecutive ABs (4 PAs) spread over the two games shown.

Youngest to appear in various All-Star Game roles:

Does anyone have any anecdotes, or other related games or accomplishments?