Baseball rivalries have a heightened importance for a tiny segment of the population that harbors passion for the sport while the rest lose interest. Then there's a slightly mentally unhinged micro-group of fans who seem to take their fandom too far, especially when alcohol is involved. On March 3, 2011, two men in Dodgers paraphanilia severely beat a Northern California paramedic named Bryan Stow outside Dodgers Stadium.

On Thursday, another incident outside of AT&T Park involving Dodgers and Giants fans resulted in the fatal stabbing of 24-year-old Jonathan Denver, whose father worked security at Dodgers Stadium.

Via ESPN:

San Francisco police say Denver, 24, was walking with his father, brother and two other people not far from the Giants' ballpark Wednesday night when their group exchanged words with some Giants fans who were leaving a nightclub.

The exchange turned physical, and Denver, who was wearing Dodgers gear, was stabbed to death.

"There is no rational explanation for this senseless act," the Dodgers said in a written statement. "The pain that this has caused his family and friends is unimaginable."

Denver attended the game with his relatives but left in the eighth inning of what turned out to be a 6-4 Giants victory. His attackers did not attend the game.

San Francisco police said Michael Montgomery, 21, of Lodi, was arrested on suspicion of homicide in connection with the fatal stabbing.