Conversation so far:
Did Tom Seaver really have 300 wins?
On August 4, 1985, Tom Seaver recorded his 300th victory at Yankee Stadium against the Yankees, throwing a complete game 4 to 1 victory.

Question: What team was he playing for at that time?
Self-contained rewrite: What team was Tom Seaver playing for at that time he recorded his 300th victory?