Atlanta’s Tony Cloninger is the only pitcher in baseball history to hit two grand slams in the same game.
The First Time
1. Roger Connor of the Troy Trojans is the first major league player to hit a grand slam, keying an 8-7 win over the Worcester Ruby Legs on September 10, 1881.
23 for Gehrig
2. Lou Gehrig hit 23 career grand slams, the most in major league history. Alex Rodriguez hit his 22nd career slam April 23, 2011.
3. Don Mattingly set a single season record with six grand slams in 1987—the only slams of his 14-year career. Travis Haffner tied Mattingly’s record in 2006.
Can’t Get Any Better Than This
4. Four players have hit grand slams in their first MLB at bat—Bill Duggleby (1898), Jeremy Hermida (2005), Kevin Kouzmanoff (2006), and Daniel Nava (2010). Kouzmanoff and Nava hit their grand slams off the first pitch.
Twice in One Inning
5. The Cardinals Fernando Tatis is the only player to hit two grand slams in one inning—both off Dodgers pitcher Chan Ho Park—on April 23, 1999.
A Series Slam
6. Cleveland’s Elmer Smith hit the first grand slam in World Series history, Game Five against the Brooklyn Dodgers in 1920. Smith’s slam was overshadowed later in the game by Indians second baseman, who turned the only unassisted triple play ever in the Series.
The Ultimate Walk-Off Slam
7. Roberto Clemente is the only player in MLB history of hit a walk-off, inside-the-park ultimate grand slam, in 1956 for the Pirates. An ultimate grand slam is a walk-off slam for a one-run victory.
Some Pitchers Can Hit
8. Tony Cloninger of the Braves is the only pitcher to hit two grand slams in a game, in 1966 against San Francisco. Yankee hurler Mel Stottlemyre is the last pitcher to hit an inside-the-park grand slam, in 1965 against the Red Sox.
An All-Star Rarity
9. Fred Lynn is the only player ever to hit a grand slam in the All-Star game. The Angels outfielder performed the feat in the 50th anniversary game in 1983.
Three in A Game
10. Only twice have three grand slams been hit in a single game — Baltimore (2) vs. Texas (1) in 1986 and Cubs (2) vs. Houston (1) the following year.