NEW YORK -- Arizona Diamondbacks ace Zac Gallen appears headed to the injured list after straining his right hamstring five pitches into Thursday night's 3-2 loss to the New York Mets.
The 28-year-old right-hander, who finished among the top five in NL Cy Young Award voting in each of the last two seasons, was scheduled to return to Phoenix on Friday for a scan.
Gallen felt the injury on his knuckle-curve that Francisco Lindor lined to center for a leadoff single.
Gallen hopped after releasing a fastball to DJ Stewart, his second batter. Manager Torey Lovullo and an athletic trainer went to the mound, and Gallen limped as he walked to the dugout.
"Hamstring grabbed on me, so I threw another pitch to see if it was severe and sense if I could keep pitching or not, if it was more like a cramp," Gallen said. "Just knew that I couldn't really keep going or if I did I would put the team in jeopardy of not giving them a chance to win."
Lovullo was forced to use his bullpen to get 24 outs from Bryce Jarvis (one inning), Brandon Hughes (1 2/3 innings), Justin Martinez (three innings), Joe Mantiply (two outs), Ryan Thompson (one inning) and Kevin Ginkel (two outs).
Lovullo said he likely would wait until results of the scan to determine a roster move. Seattle's Triple-A team, the Reno Aces, was at home, complicating bringing a minor leaguer to New York as a replacement for Gallen, who is 5-2 with a 3.12 ERA in 11 starts.
"We're going to get him back to Arizona. We feel comfortable doing that and we feel like that's the safest bet to get the right evaluation and get more detail on exactly what he's feeling," Lovullo said. "It's not great news. I'm not going to lie, and we will eventually find out what the solutions are."
Gallen left a start on April 26 at Seattle with a man on and no outs in the sixth after a fastball to Julio Rodriguez because of right hamstring tightness, and said he felt tightness akin to a cramp during the third or fourth inning of a May 18 outing against Detroit.
"The one in Seattle was a little bit more minor," Gallen said. "This one, it's a mild, I guess. It felt similar to kind of what I did in '21."
Gallen said the area of hamstring trouble was slightly different all three times this season.
"Just up and down," he said.
Gallen missed two weeks because of his right hamstring in July 2021, when he didn't pitch between July 2 and 17, and he also experienced a hamstring issue in 2019.
Gallen hoped any layoff will be similar to the one in 2021.
"It's been three years now, so maybe my memory's kind of a little bit fogged on that but, yeah, that one, it didn't feel great, either, and wound up missing I think a start or two," he said.
NL champion Arizona matched its season-low of six games under .500 at 25-31. The Diamondbacks already were missing right-hander Merrill Kelly, sidelined since April 15 by a strained right shoulder, and left-hander Eduardo Rodriguez, who signed an $80 million, four-year contract as a free agent and hasn't pitched this season because of a strained pitching shoulder.
Arizona wasted a two-run lead and lost its fourth straight. The Diamondbacks have scored nine runs in their last six games.
"They're absorbing it right now, and it's painful. It hurts," Lovullo said. "It hurts a lot because we care, and I'm OK with that. But at some point we got to be able to cycle through and understand why we lost this baseball game. There were some things we did wrong, and we just got to find a way to make them right, and we're going to be just fine."