PORT ST. LUCIE — Brooks Raley is keeping his arm strong by continuing to play catch, but his left hamstring hasn’t progressed to the point he’s ready to get back on a mound. 

The lefty reliever won’t pitch in a game for at least a week, according to general manager Billy Eppler, after returning from the World Baseball Classic (before the tournament started) with the injury. 

While Raley considers the Opening Day roster a “strong possibility,” he won’t risk worsening the hamstring by pushing too hard to be ready on March 30. 

Raley was one of four Mets players selected to Team USA, along with Pete Alonso, Jeff McNeil and Adam Ottavino.

He isn’t sure how the hamstring injury occurred. 

“It could have been a little bit of dehydration, it could have been a little bit excited and flights and all that kind of stuff so there are some variables,” Raley said. “But we’ll kind of progress through this and see how we do.” 

Zach Greene cleared waivers and returned to the Yankees.

The right-handed reliever, who was selected in the Rule 5 draft, pitched to a 23.63 ERA in his five appearances this spring for the Mets.

To keep Greene in the organization, the Mets would have had to place him on the major league roster and let him stay there all season. 

Starling Marte was a late addition to the lineup, two days after he was beaned by a 93 mph fastball.

Marte, who was under observation for a possible concussion, started in right field and finished 0-for-2. 

Kodai Senga threw a bullpen session and appears on course to make his next start.

The right-hander was scratched from his Saturday outing because of tendinitis at the base of his right index finger.