No. 1983.07.24 · Free Agency Era
The Pine Tar Game
George Brett's go-ahead homer was taken off the board because there was too much pine tar on the bat. The league president put the homer back.

George Brett's pine-tar bat on display at the Henry Ford Museum in 2006, beside Mark McGwire's body armor. The photograph is of the bat years later, not the July 24, 1983 at-bat.
Dave Hogg, CC BY 2.0, via Wikimedia Commons.
July 24, 1983, Yankee Stadium. George Brett hit a two-run homer off Goose Gossage in the ninth, and Kansas City took the lead. Billy Martin asked the umpires to look at the bat. The rule limited pine tar to 18 inches up the handle. Tim McClelland laid the bat across the plate, found tar well beyond the limit, and called Brett out. Brett came out of the dugout in the eruption that became the photograph.
American League president Lee MacPhail overturned the call. The pine-tar rule, he wrote, was about keeping the ball clean, not about canceling a home run after it had left the park. The game was resumed on August 18 from the moment after the homer, with Brett having been ejected for the argument and therefore not on the field. The Royals won, 5–4.
Martin had the rule on his side for an evening. MacPhail decided the rule had been pointed at the wrong thing. The resumed game took a few minutes. The argument took the rest of the summer.
Film
The pine tar incident
George Brett's home run is ruled an out because of pine tar, and he charges from the dugout.
Watch on MLB.comRelated entries

Denkinger Calls Orta Safe
With St. Louis one out from a championship, Don Denkinger called Jorge Orta safe at first. Replays showed he was out. The Cardinals never got the inning back.
Kansas City Royals · St. Louis Cardinals

Galarraga's Imperfect Game
Armando Galarraga was one out from a perfect game when Jim Joyce called Jason Donald safe. Joyce saw the replay, and said he had missed it.
Detroit Tigers · Cleveland Indians
No. 1994.07.15
1994
Albert Belle's Corked Bat
Umpires confiscated Albert Belle's bat in Chicago. A teammate crawled through the ceiling to swap it, and the replacement had the wrong name on it.
Cleveland Indians · Chicago White Sox