This isn't so much for the individual incident—which was admittedly minor—but for the impact it had.
The Red Sox had been beating up on the Rays in their first few years in the league and Pedro had developed a reputation as someone who wasn't afraid to plunk the opposition. Without having to worry about retribution, the Red Sox pitcher would go through periods where he would bean someone almost on a weekly basis.
The Tampa Bay Devil Rays were no exception to this, apparently, and Pedro hit Williams when he came up and in on the outfielder. A furious Williams charged the mound, the benches emptied, and seven or eight Rays were suspended for their part in the brawl.
The rivalry simmered throughout the year and the animosity eventually grew to one of the best in the league.
Scott Kazmir and Bronson Arroyo picked up the charge for each team when they took it in turns to go after each other's hitters, and Lance Carter threw at Manny, gave up a homer to him on the very next pitch and then threw behind Big Papi.
According to Steve Schaefer, Arroyo later ignited another benches-clearing fracas when he drilled Chris Singleton. And to think it all began with Pedro. Did anyone notice he barely hit a batter when he came to the National League and had to step into the batter's box? Coincidence?
Odds: Williams has three inches and 20 pounds on Pedro, and even though he has a couple years on the veteran hurler, Pedro is probably in slightly better shape today. But Williams was a .200 hitter over his final five seasons, so Pedro shouldn't be too worried about the former Blue Jay hitting anything.
Pedro -110, Williams +105