Justin Verlander won’t be the only former Tiger making a return to the Mets’ rotation in Detroit this week.

The game that was postponed by rain Saturday against the Braves won’t be made up until August, so Max Scherzer’s 10-game ban for violating MLB’s rules on foreign substances now will be extended until at least Tuesday, when the Mets open their three-game series at Comerica Park.

Scherzer has been slotted to pitch the series finale against the Braves on Monday at Citi Field.

And given the ominous forecast for Sunday, it’s possible Scherzer might not be eligible to pitch again until Wednesday.

Before his last outing on April 19 — which resulted in an ejection for using a sticky substance — Scherzer had been pushed back three days in the rotation because of discomfort under his right scapula.

Verlander is expected to make his season and Mets debut either Wednesday or Thursday in Detroit after he reported no issues following a minor league rehab start with Double-A Binghamton on Friday.

Verlander, sidelined since the spring with a teres major strain near his right armpit, pitched 4 ²/₃ scoreless innings in the 69-pitch outing on Friday and said he thought he’d be ready to start for the Mets whenever they asked.

Manager Buck Showalter said before the Mets’ rain-shortened loss to Atlanta on Friday at Citi Field that he wanted to check with Verlander, as well as pitching coach Jeremy Hefner and the training staff, before making anything official. He added the plan was for Verlander to start in Detroit.

“I’m very excited to finally have a chance to pitch for the Mets,’’ Verlander told reporters. “It’s not the way I envisioned starting my career here. Unfortunately, these things happen. I’m doing everything I can to be back and be successful. I was hoping it would be quicker, but it just didn’t cooperate.”

Want to catch a game? The Mets schedule with links to buy tickets can be found here.

Without Verlander and Jose Quintana so far this season — and more recently, with Scherzer and the injured Carlos Carrasco also out — the Mets’ rotation has been shaky.

Showalter wasn’t looking forward to the prospect of a doubleheader this weekend when the possibility was raised to him on Friday.

The Mets, as of Saturday, hadn’t named a starter for their game Sunday, though the scheduled starter for Saturday, Tylor Megill, is a possibility.

For Monday, the Mets could go with Jose Butto or a bullpen game.

Atlanta is set up with Spencer Strider, who had been slated to start Saturday, going Sunday and Charlie Morton or Bryce Elder finishing the series.

The Mets had hoped David Peterson would be a valuable fill-in for the rotation, but after another rough outing in the loss to the Braves on Friday, the lefty was optioned to Triple-A Syracuse, the team announced Saturday.

Peterson has struggled in most of his six starts this season, with a 7.34 ERA. He pitched well for four innings Friday before allowing four runs in the fifth.

The bullpen also took a hit Saturday, as left-hander Brooks Raley was placed on the 15-day IL with left elbow inflammation, retroactive to Friday. Raley had pitched eight scoreless innings over his previous 10 appearances before allowing two runs in his last outing.

To take Raley’s spot in the bullpen, right-hander John Curtiss was recalled from Syracuse.

Adam Ottavino was also reinstated from the paternity list, taking Peterson’s spot on the roster.

The game postponed Saturday due to rain will be made up as part of a split doubleheader Aug. 12 (also a Saturday), with the first game scheduled for 1:10 p.m. and the second at 7:15 p.m.

Fans who paid for tickets to the postponed game can use them for the first game Aug. 12 or exchange them for a ticket comparable in price and location to another regular-season game at Citi Field — with the exception of June 3, which is the Mets’ Hall of Fame Ceremony, and the June 13-14 Subway Series against the Yankees.