Edwin Diaz of Team Puerto Rico is carried off the...

Edwin Diaz of Team Puerto Rico is carried off the field after sustaining an injury while celebrating a 5-2 win against Team Dominican Republic during their World Baseball Classic Pool D game at loanDepot park on Wednesday in Miami, Fla. Credit: Getty Images/Al Bello

PORT ST. LUCIE, Fla. — The Mets’ worst nightmare about having their star players participate in the World Baseball Classic appears to have come true.

All-Star closer Edwin Diaz injured his right knee in the on-field celebration after he recorded the final out of Puerto Rico’s 5-2 victory over the Dominican Republic in Miami on Wednesday night. 

Diaz suffered the injury as he was piled on by his jubilant teammates as Puerto Rico clinched a spot in the WBC quarterfinals.  

Diaz stayed down for a while as his teammates parted once they realized he was hurt. Diaz got up but was unable to walk off the field under his own power. He had to be helped to the dugout area by a coach and a trainer as he was unable to put any weight on the leg.

Diaz was put in a wheelchair just outside the dugout and was helped into the concourse beneath the stands. 

Diaz’s brother, Reds pitcher Alexis Diaz, could be seen crying. Alexis Diaz is also a member of Puerto Rico’s WBC squad.

The Mets said it was a right knee injury and that imaging would be conducted Thursday.

The Mets re-signed Diaz to a five-year, $102-million contract in the offseason after he saved 32 games and struck out 118 batters in 62 innings last season. 

If Diaz is unable to start the season because of the injury, the Mets could use David Robertson as his replacement at closer. 

The Mets — like every big-league club — have been holding their breath as their players participate in the WBC.

Lefty reliever Brooks Raley suffered a hamstring injury while getting ready to play for Team USA and returned to the Mets. His status for Opening Day is in doubt.

The Mets have seven big-leaguers competing in the WBC: their entire starting infield in Pete Alonso and Jeff McNeil (USA), Francisco Lindor (Puerto Rico) and Eduardo Escobar (Venezuela); their new catcher, Omar Narvaez (Venezuela); and relievers Adam Ottavino (USA) and Diaz.

Fears about injury because of players having to ramp up for playoff-type games in March run through MLB clubs whenever the WBC comes around. But a star getting injured celebrating a victory was probably not on anyone’s mind until Wednesday.

Brandon Nimmo, who played for Italy in the 2017 WBC but declined to play this year, told Newsday earlier this week of his teammates: “For me, they're playing playoff baseball right now. As long as they come back to us healthy, I’m happy. They're around some of the best players in the game and they're going to pick up stuff and it's going to be really great. I just want them to come back to us healthy.” 

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