There hasn’t been anyone named “Groundhog” in the Majors or Minors, but there WAS a Frank “Groundhog” Thompson in the Negro Leagues. I’ll let Baseball Reference explain:
Groundhog Thompson was a Negro League pitcher for ten seasons. Thompson’s appearance (far from handsome) drew considerable notice, just like Don Mossi in the majors or Agapito Mayor in Cuba. He had a chipped tooth, a harelip and walleye and was short and squat.
The website “PitchBlackBaseball” described the 5’2″, 135 (or maybe 150) pound Thompson thusly:
“Groundhog” got his nickname because, well, he sort of looked like a groundhog. One thing is for certain – he didn’t look like a professional baseball player. One reporter described him on the mound as looking like the tip of a sweet potato sticking out of the ground.
This might be an insult to groundhogs . . .
Regardless, it turns out that the diminutive Thompson could really pitch. In 1953, at age 36, he turned in one of the finer seasons in Negro American League history:
1953 Negro American League
Finals Pitching Stats (100 or more innings pitched)
GAMES: 23 (first)
COMPLETE GAMES: 14 (second)
LOSSES: 6 (third)
WIN%: .700 (second)
INNINGS PITCHED: 152 (first)
WALKS: 42 (fourth)
STRIKEOUTS: 113 (first)
ERA: 2.31 (second)
The only other “Groundhog”-tagged player I could find was the already distinctively-named Orval Overall, a burly 6″2″, 215 pound pitcher for the Cubs and Reds in the early 1900s. Baseball Reference doesn’t have any “Groundhog” attached to Mr. Overall, but SABR’s Baseball Biography Project does:
Later called the “Big Groundhog” because of his birthday, Orval Overall was born on February 2, 1881, in Farmersville, California, a small agricultural community just outside of Visalia.
So, one can only wonder if those who knew Mr. Thompson or Mr. Overall believed there would be six more weeks of Winter if the humanized version of the “Groundhog” saw his shadow.