From rotoworld:
A source tells Mike Salk of 710 ESPN in Seattle that Milton Bradley left the team in the middle of Tuesday's game against the Rays.
Bradley was frustrated after striking out looking with the bases loaded in the bottom of the sixth inning. He yelled at the umpire from the bench until Mariners manager Don Wakamatsu warned him to settle down. Just minutes later Bradley reportedly told Wakamatsu, "I'm packing my stuff. I'm out of here." Mariners General Manager Jack Zduriencik didn't address the matter specifically on Wednesday, other than to say something that happens between the manager and his players should be handled internally. We're guessing that Wakamatsu might not have to worry about Bradley much longer.
Source: MYNorthwest.com
It's cliche to talk about certain guys having anger management issues. But a guy like Zambrano has a temper, not an "issue", so much. He'll be willing to admit that he's overreacted, he'll apologize and seem to have some perspective. Bradley is something different entirely, truly pathological. If he screws this up, I seriously doubt he gets another chance anywhere.