Final answer:
George Brett of the Kansas City Royals was accused of using too much pine tar on his bat on July 24, 1983, causing a game-winning home run to be nullified against the New York Yankees.
Step-by-step explanation:
The player who was accused of using too much pine tar on his bat on July 24, 1983, causing a game-winning home run to be nullified, was George Brett of the Kansas City Royals. In a game against the New York Yankees, Brett hit a home run off of relief pitcher Goose Gossage, but it was later determined that the amount of pine tar on Brett's bat exceeded the length limit specified by the rules. The run was disallowed, and the game was finished at a later date with the Yankees winning.