Jon Rauch — 6'11", 290 lb

Jon Rauch was selected by the Chicago White Sox in the 3rd round of the 1999 MLB Draft out of Morehead State. He’s listed at 6’11”, 290 lb — the tallest player ever to appear in a major-league game. He debuted with the White Sox in April 2002 and became a full-time relief pitcher in 2005. Career: 12 MLB seasons, 8 teams (White Sox, Expos/Nationals, Diamondbacks, Twins, Blue Jays, Mets, Marlins), 49 saves, 4.10 ERA across 561 appearances.

Rauch was tall enough that his control on the mound was a perpetual challenge — his strike zone (the area between his knees and chest) was significantly higher than every other player’s, which created different umpire calibration. Rauch retired in 2013 at age 35. He’s currently a pitching coach in the Boston Red Sox system.

Randy Johnson and Chris Young at 6'10"

Randy Johnson — the Big Unit — is the most-famous tall MLB player ever at 6’10”. He won 5 Cy Young Awards (1995, 1999-2002), pitched a perfect game in 2004 at age 40, threw a no-hitter in 1990, was a 10-time All-Star, and is in the Hall of Fame (2015). His 4,875 career strikeouts are 2nd all-time. The combination of his height and the angle his fastball came in at made him the most-feared left-handed pitcher of his era.

Chris Young (the pitcher, not the outfielder) was also 6’10”. He pitched 13 MLB seasons (2004-17) for six teams, including the Padres, Mets, and Royals. Won the 2007 NL Comeback Player of the Year. Won the 2015 World Series with the Royals. He’s now the General Manager of the Texas Rangers — and was the GM who led the Rangers to the 2023 World Series title.

Other notably tall MLB players

Sean Hjelle (San Francisco Giants, 2022-present) — listed at 6’11”, joining Rauch as the only co-tallest active player. Eric Hillman (1990s Mets pitcher) — 6’10”. Andrew Brackman (Yankees pitcher) — 6’10”. Andrew Sisco (2005-08 reliever) — 6’10”. Mike Smithson (1980s starting pitcher) — 6’8″.

Among position players (not pitchers), the tallest in MLB history is Frank Howard at 6’7″ (Senators/Rangers, 1958-73). Howard was a 4-time All-Star and twice led the AL in HRs. Modern position players: Aaron Judge (6’7″), Cody Bellinger (6’4″), and Pete Alonso (6’3″). The historical pattern holds — pitchers can be much taller than position players because their movement requirements are different (a pitcher has 5-10 second action windows; position players need to cover ground).

Background facts cross-referenced with the Wikipedia article on Jon Rauch and Pro-Football-Reference / Basketball-Reference public records.