Pete Alonso started Thursday’s game with a mustache, but ended it cleanly shaven.

“I had very terrible at-bats before so I was like, ‘The mustache needs to go,’ as simple as that,” Alonso said after the Mets beat the Diamondbacks 11-1 at Citi Field.

Alonso, who finished 0-for-5, said it was after his third at-bat that he took the razor to his mustache. He said he’s previously taken such action in an attempt to change his fortunes.

“Baseball players are very superstitious,” he said.

A night earlier, Alonso distributed specially designed cleats to his teammates commemorating 9/11. The slugging first baseman did so without consulting MLB, which prohibited the Mets from wearing caps honoring first responders. Alonso said he has not heard from MLB regarding the cleats.

“I haven’t, which is a good thing,” he said.

Dominic Smith began increasing his workload in recent days as he attempts to return from a stress fracture in his left foot. Smith has been participating in agility drills and hitting off a tee. He is eligible for removal from the 60-day injured list on Sept. 25 — which would allow him to play in the final week of the season — but would have to be cleared medically after receiving a scan on the foot.

Robert Gsellman continues to play catch on flat ground with the hope he can still pitch this season. The right-hander has been sidelined with a lat tear since Aug. 14.

“I’m missing all the fun,” he said.

Steven Matz is the Mets’ nominee for the Roberto Clemente award, given annually to baseball’s top humanitarian. Matz remains active in raising money for families of first responders. The winner is announced during the World Series.

Michael Conforto’s seventh-inning blast gave the Mets teammates with 30 homers in the same season for the eighth time in their history. Alonso leads the team with 47 homers. Yoenis Cespedes and Curtis Granderson each reached 30 homers with the Mets in 2016.

Robinson Cano finished 1-for-3 with a homer, giving him at least one hit in his last 11 starts. Over his last 12 games he is 19-for-40 (.475) with four homers and eight RBIs.

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