George Steinbrenner makes a cameo appearance in the season 7

Worst celebrity cameo? : r/seinfeld

Cameo Appearance by the real George Steinbrenner that was ultimately cut from 'The Invitations'. I'm glad they didn't end up using it since it would've ruined the whole bit of him sitting

George Steinbrenner: Hero or villain?

George Steinbrenner makes a cameo appearance in the season 7 finale. But the scene was deleted. : r/seinfeld

15 Larry David Cameos on Seinfeld

We're winners! We don't sit with losers!” - New York Yankees legend George Steinbrenner once acted for the global hit show Seinfield until his cameo was removed from the final release

Damn Yankees!: The Most Memorable Appearances by NY Yankee Players on Seinfeld, News, Scores, Highlights, Stats, and Rumors

George Steinbrenner – Society for American Baseball Research

Fans mourn death of Yankees' owner - Statesboro Herald