PHILADELPHIA — The Mets are set to expand their roster Sunday, with Brandon Nimmo as a prime candidate to rejoin the team.

Without divulging the organization’s plan Saturday, manager Mickey Callaway indicated Nimmo was a possibility to return, as the outfielder prepared to play a rehab game for Triple-A Syracuse. Nimmo impressed team officials the previous night with a diving catch in the outfield that showed his previously injured neck isn’t a factor. Nimmo has been on the injured list since May 21 because of a bulging disk in his neck.

“We are going to know that Nimmo has had almost the full season off,” Callaway said before the Mets beat the Phillies, 6-3. “We have to take that into account and have to understand who has been up here has been getting the job done since the All-Star break and doing well. There will be times when he starts and times when he is coming off the bench, and I think we need to keep it fluid and see how everybody is clicking and how everybody is doing.”

It is unclear whether Jed Lowrie, who still hasn’t played for the Mets this season after arriving on a two-year contract worth $20 million last winter, is a possibility to join the team Sunday. Lowrie was expected to play third base and second base in a rehab game for Syracuse.

Tomas Nido, who has spent the past week on the concussion list, could return to give the Mets a third catcher.

Jeff McNeil was absent from the starting lineup Saturday as part of a scheduled day off. Callaway said there was some thought about giving McNeil the day off Friday, but didn’t want him absent from lineup the same night as Wilson Ramos, who was back behind the plate Saturday.

Ramos went 4-for-5 with an RBI and two runs to extend his hitting streak to 24 games, during which he is 41-for-92 (.446) with three homers and 17 RBIs.

He said he first became aware of Joe DiMaggio’s record hitting streak a few years ago.

“I had 19 straight with the Nationals,” Ramos said. “As soon as I found out [the record] was 56, I said, ‘No way, no chance.’ ”

Ramos’ streak is MLB’s longest in a single season since Freddie Freeman hit in 30 straight games in 2016.

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