“We hope it’s not much,” Girardi said of the injury. “We won’t know until tomorrow.”

Originally, the Yankees had planned for Jeter to return from his Class AAA minor league rehabilitation assignment in Pennsylvania on Friday. But when Travis Hafner and Brett Gardner both sustained foot injuries Wednesday night, they decided to bring Jeter back a day early. Could that have contributed to Jeter incurring an injury before he could even get nine innings under his belt? Jeter said no.

“I’ve been running all over the place the last three weeks,” he said of his rehabilitation work.

Jeter, who had been antsy to rejoin the Yankees, learned from General Manager Brian Cashman at about 11 p.m. Wednesday that he would finally be activated. He had already arrived at his hotel in Moosic, Pa., and quickly packed for the drive back to New York. He arrived in Manhattan around 2:30 a.m. but did not get to bed until 4. He woke up just two and a half hours later, unable to get back to sleep because of his early-morning rehabilitation schedule plus his excitement over the impending day.

Hours later, the first reaction from the crowd of 40,381 came when he ran in the outfield during pregame warm-ups. When he strode to the plate in the first inning, batting second, the fans gave him a sustained standing ovation.

Jeter had planned since Wednesday to swing at the first pitch he saw, and with the Yankees already trailing, 3-0, he followed through. He hit a bouncer to third base, sprinted down the line and safely reached first. He went to third on a single by Robinson Cano, still showing no ill effects from his ankle injury, and then scored on a sacrifice fly.

It was not too dissimilar from his nine at-bats in the minors (he went 1 for 9), but for the first time since last October, it mattered.

“It’s a huge difference,” he said. “No disrespect to any rehab assignment that you do, but it’s Yankee Stadium. I was nervous going into the game. It’s almost like opening day for me even though, what are we, in July now? I’ve lost track of the months. So it felt good to be out there, and the fans were great.”