Conversation so far:
Why did Roger Clemens return to the Yankees?
Roger Clemens unexpectedly appeared in the owner's box at Yankee Stadium on May 6, 2007, during the seventh-inning stretch of a game against the Seattle Mariners.

Question: Why did he appear there?
Self-contained rewrite: Why did Roger Clemens appear unexpectedly in the owner's box at Yankee Stadium on May 6, 2007, during the seventh-inning stretch of a game against the Seattle Mariners?