PHOENIX -- The D-backs beat the Pirates, 11-1, on Wednesday afternoon at Chase Field to win the three-game series, but now they have to hope they haven’t lost their ace.

Zack Greinke, who allowed just four hits over 7 2/3 scoreless innings, was forced to leave the game with abdominal tightness in the top of the eighth with a 2-2 count on Chris Stratton. After a brief discussion on the mound with the training staff, Greinke was pulled and replaced by Yoshihisa Hirano, who struck out Stratton to end the inning.

Arizona manager Torey Lovullo said Greinke is set to have an MRI on Friday, which will help determine the extent of the injury.

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“I don’t know,” Greinke said when asked how the abdominal muscle felt. “We’ll find out in a couple days. It could be better. Maybe if I did it over again, I’d throw a 75-mph fastball to the pitcher to see what happens. I definitely didn’t want to throw another pitch hard and run a chance of pulling more than it did.”

When Greinke first felt the discomfort on his second-last pitch, his first thought was that it was his oblique muscle, which forced him to miss significant time in 2016.

“I didn’t want to push it and hopefully it wouldn’t be as bad [as his oblique injury],” Greinke said. “But it seems to be in a different spot. Last time it was six weeks, so hopefully this won’t even be six days.”

Greinke tweaked his back a bit in the fourth inning when he turned to take a pitch while at the plate. He stretched a bit and remained in the game to draw a walk, steal a base and score a run without any further issue from the back.

The back thing has happened a bunch for Greinke this season, but he said that “it gets better after two seconds usually.”

So just how concerned is Lovullo about Greinke’s abdominal injury?

“It’s hard to say right now,” he said. “You’re asking me and I’m always in the clouds and optimistic about things. I’m going to, obviously, hope for the absolute best.”

The D-backs certainly have to hope that Greinke does not have to miss any significant time, as he is in the midst of another outstanding season.

After struggling on Opening Day against the Dodgers when he allowed seven runs in 3 2/3 innings, Greinke has gone 6-0 with a 1.92 ERA.

It was vintage Greinke on Wednesday, as he allowed just one Bucs hitter to advance as far as second base. That was Josh Bell, who doubled in the second and advanced to third on a groundout. Greinke did not allow a walk and struck out five.

“He means so much to this rotation,” Lovullo said. “I went to bed last night thinking, ‘Zack’s throwing in a really, really important baseball game and we’re going to get the absolute best effort from him and it’s going to be very, very efficient.’ He’s our guy and we know that.”

It was a bad day overall on the injury front for Arizona. In addition to Greinke, left fielder David Peralta left the game in the sixth with right trap tightness.

That, Lovullo said, did not appear to be serious. Peralta is expected to be fine with some therapy in the training room.

Meanwhile, right-hander Taijuan Walker, who is working his way back from Tommy John surgery last May, was removed from his extended spring camp 17 pitches into it when he had some right shoulder soreness.

“As a precaution, he was removed from the game, which I feel was the right thing to do,” Lovullo said. “He is getting an MRI right now.”