Harper pointed the bat toward Strickland, charged the mound and fired his batting helmet wide of the pitcher. They started to swing away and they each connected as the benches and bullpens emptied. At least two Giants players forcefully dragged Strickland from the middle of the brawl all the way into the dugout.
Strickland and Harper were both ejected from the game.
This is Harper's ninth career ejection and Strickland's first.
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The Associated Press contributed to this story.