On Saturday night, in a game against the Bradenton Marauders (Pirates), Mientkiewicz and opposing manager Frank Kremblas got into a little fracas during a benches-clearing incident. Here's video from the Fort Myers News-Press, which is passed along by Brandon Warne of 1500 ESPN:
Mientkiewicz is #16 in white. You can see him getting pushed around and held up against the fence. Kremblas is #3 in road gray, but I didn't see him anywhere in the video. He could be one of the guys pushing Mientkiewicz.
According to Warne, the whole thing started with a simple beaning. A Fort Myers pitcher plunked a Bradenton batter and that was that. Off they went.