Boston ? Police are looking for witnesses to a fight between two Yankees and a Fenway Park worker in the New York bullpen during Game 3 of the AL championship series before deciding whether to file charges.

“They’re looking for people to come forward,” officer Michael McCarthy, a police spokesman, said Sunday.

Grounds crew worker Paul Williams and Red Sox officials contend Yankees pitcher Jeff Nelson and outfielder Karim Garcia attacked Williams during the ninth inning Saturday night. The Yankees denied the players were to blame.

With tempers already high following a bench-clearing melee earlier in the game, Nelson was annoyed that Williams was cheering for the Bosox while he was in the New York bullpen.

“He was standing in our bullpen waving the rally flag,” the reliever said, following New York’s 4-3 win. “I told him, ‘If you’re rooting for the Red Sox, why don’t you go in their bullpen.’ He jumped in my face and tried to take a swing at me.”

Assault charges could be filed against the two players.

Police refused Sunday to release their report on what happened. It isn’t clear how long the investigation would take, McCarthy said.

After Nelson confronted Williams, several Yankees surrounded him. Garcia, the right fielder, jumped over the fence and hurt his left hand. He was removed from the game with the hand wrapped.

Williams had cleat marks on his back and his arm, Red Sox spokesman Charles Steinberg said.

Williams was wearing a neck brace when he left the hospital Sunday morning. A hospital spokeswoman wouldn’t release details of his injuries.

Williams acknowledged pumping his fist twice while holding a white towel, Steinberg said.