PHILADELPHIA — The Mets could be facing another significant roster decision as soon as Monday. 

Mark Vientos is on the verge of coming back from a right hamstring strain that has sidelined him for nearly three weeks. Manager Carlos Mendoza mentioned before Sunday’s game that the third baseman might be ready to rejoin the team for the upcoming four-game series against the Braves at Citi Field.

Vientos played Sunday in a minor league rehab game for Triple-A Syracuse and went 1-for-5 as the starting third baseman.

Vientos is 2-for-17 (.118) over four games in his rehab assignment. 

“We’ll evaluate if he needs more at-bats to get his timing right, but his health remains the top priority,” Mendoza stated prior to the Mets’ 7-1 defeat to the Phillies at Citizens Bank Park. “If he’s physically prepared, then we can move on to the next step.” 

Vientos’ return will add to an already crowded infield, potentially sending Ronny Mauricio, Brett Baty, or Luisangel Acuña back to Syracuse. 

Acuña, who started at second base Sunday, has served as a late-inning defensive replacement and pinch-runner.

Baty and Mauricio can each play third base and second. Once Vientos returns, the Mets might want Mauricio playing every day at Syracuse, as his at-bats figure to be reduced with Vientos’ return.

Mauricio missed all last season rehabbing from multiple knee surgeries. 

Baty, Mauricio and Acuña have struggled offensively. 

Vientos has dealt with his own offensive struggles — he’s produced a .230/.298/.380 slash line with six homers and 21 RBIs in 53 games this season.

He injured the hamstring running to first base at Dodger Stadium on June 2. 

The Mets entered play 61-for-71 (85.9 percent) in stolen base attempts this season, which was the highest rate in MLB.

The Mets were one of eight teams with four players (Francisco Lindor, Juan Soto, Acuna and Tyrone Taylor) to have at least eight stolen bases this season. 

The Mets’ seven-homer barrage Saturday marked the fifth time in franchise history the team hit at least that many homers in a game. All the occurrences have been at Citizens Bank Park.