Bonds passes Aaron as baseball’s home run king

SI.com

On August 2 I linked to a baseballmusings.com chart showing the Mike Bacsik was the pitcher who threw to contact most this year, and noted the odd spell he seemed to have over Barry Bonds (who was 1-15 against Bacsik in his career at that point–that one hit a homer).

Since then Bacsik threw the pitch which Bonds hit to break the record. What are the odds of that?