The small city of Appleton, Wis., played host to one serious display of star power in the summer of 1996.

As part of a barnstorming tour, the Ken Griffey Jr.– and Edgar Martinez-led Seattle Mariners stopped by Appleton for an exhibition against the Wisconsin Timber Rattlers, the team’s Class-A affiliate at the time. When rain put the game on hold, the players decided to give the fans a show by holding an impromptu home run derby.

Among the contestants were Griffey (then at the height of his popularity) and a young Alex Rodriguez, but an unknown Timber Rattlers slugger wearing No. 47 stole the show. That man was David Ortiz, and even a hot-shot rookie like A-Rod was unable to contain his bewilderment at the punishment Ortiz was inflicting on the baseball.

Check out 20-year-old Big Papi’s display in the video below, with a hat tip to Grantland for digging it up.