NEW YORK -- Michael Conforto’s standout season came to a premature end on Thursday, as the Mets placed him on the injured list due to left hamstring tightness. The team called up Luis Guillorme to replace Conforto on the roster for the final four games.

Conforto began experiencing hamstring discomfort in the later innings of Sunday’s game at Citi Field. He sat out the next two games, then returned on Wednesday as the Mets’ designated hitter. But the issue resurfaced as Conforto tried to beat out an eighth-inning groundout in that game, leading the Mets to place him on the IL.

So ended the best season of Conforto’s career, at least on prorated basis. Conforto set career highs in average (.322) and on-base percentage (.412), sacrificing some pull power for more of an all-fields approach. But he still hit nine home runs, which would equate to 24 over a full season, while slugging .515.

“He had a great regular season,” manager Luis Rojas said. “He was solid throughout. … Offensively, his numbers are there. He was unbelievable. He did a great job of just improving some of the parts that he said he wanted to improve in his game offensively, and then he also improved some of the parts that he wanted to improve defensively. He made some incredible plays out there in the outfield. Just a great overall season on the field for him.”

Rojas also noted that Conforto is “growing more and more” into a clubhouse leader, often mentioned along with Pete Alonso as a future Mets captain. For that to happen, Conforto would need to sign a long-term extension, which he says he is open to doing if prospective incoming owner Steve Cohen wants to negotiate.

“I love it here,” Conforto said earlier this week. “This is everything I know.”

With Conforto out of Thursday’s lineup, Jeff McNeil started again in right field, where he is likely to remain the rest of the season. The injury also cleared roster space for the Mets to take another look at Guillorme, a standout middle infielder who hit .347 in 26 games before trade acquisition Todd Frazier squeezed him out of a roster spot.