Mets hiding cards on how they’ll shuffle Jake, Taijuan

PHILADELPHIA — Max Scherzer will start Monday. That is as much as the Mets know for sure about their rotation.

Taijuan Walker worked out at Citizens Bank Park on Sunday, including participating in pitcher fielding practice, in which he came off the mound to field balls.

Buck Showalter said the Mets were trying to simulate what caused the back spasms that forced him from his start last Tuesday, after which an MRI exam found a bulging disc.

“Everything went real well today,” the manager said about Walker, who was scratched from his scheduled start Sunday, before the Mets beat the Phillies, 10-9, to win the series.

Showalter has said Walker could rejoin the rotation as soon as Tuesday, which is the scheduled finale of the two-game set at Yankee Stadium. Jacob deGrom is the scheduled Tuesday starter, and while the co-ace threw before the game Sunday, the Mets could push him back to provide more than the usual four days’ rest.

Showalter said they will wait to see how Walker feels Monday morning before reaching a decision.

If deGrom pitches Tuesday and on normal rest Sunday against the Rockies, he would miss next week’s series at Citi Field against the Dodgers. The Mets are 6 ½ games behind the Dodgers for the best record in the National League.

Showalter said that is not a consideration.

“It’s about what’s best for Taijuan and Jake,” he said. “Where they fall, they fall.”

➤ It was a busy day of injury updates. Eduardo Escobar, who is dealing with an oblique strain, is “doing well” and almost pain free, Showalter said. The infielder is eligible to return from the injured list Friday, and Showalter said he should hit that target.

Tommy Hunter is “close” to being activated, Showalter said. The reliever has missed two and half weeks with lower-back tightness.

Tomas Nido is making progress “slowly,” Showalter said. Nido is on the COVID-19 list and last played Aug. 13. Showalter said the catcher may require a rehab assignment because “you don’t go from this illness to catching nine innings in the big leagues right away.”

The Mets placed righty Stephen Nogosek on the 15-day IL with a left oblique strain.

➤ The Mets added a lefty reliever to their big league roster, optioned another and cut a third.

Nate Fisher was selected from Triple-A Syracuse and immediately helped by throwing three scoreless innings. Rob Zastryzny, who pitched an inning in Saturday’s doubleheader, was sent back to Syracuse. Sam Clay, who also pitched Saturday, was designated for assignment.

Another lefty, Joey Lucchesi, began a rehab assignment with Low-A St. Lucie. Lucchesi threw 15 pitches in an inning in which he allowed an unearned run on one hit and one walk.

➤ The Mets lost Patrick Mazeika, who had been DFA’d last week, to the Giants, who claimed the catcher off waivers.