TORONTO — The challenge for the final 12 games of the season is big for the Yankees.

They must establish home-field advantage throughout the postseason and incorporate major missing pieces who are returning: pitchers Luis Severino and Dellin Betances, slugger Giancarlo Stanton and catcher Gary Sanchez.

It’s a giant jigsaw puzzle.

Big names joining big names who are producing in a big way. And Stanton is the big unknown.

The former MVP has only nine games, 38 plate appearances and one home run to his name this season. He has not played in a major league game since June 25 because of a variety of injuries, the latest a knee injury.

This year, he has had just 38 plate appearances. Last year, he had 38 home runs.

The calf injury to Mike Tauchman changed the need, because an outfield of Tauchman, Brett Gardner and Aaron Judge would have worked just fine for the Yankees, who upped their record to 98-52 Saturday by blasting the Blue Jays out of Rogers Centre, 13-3, with Gardner hitting his 24th and 25th home runs of the season.

Judge offered these words of encouragement on Stanton’s return this coming week:

“To be honest, maybe going into it, it might have been Tauchman, Gardy and me in the outfield with Stanton DH-ing. We got Edwin [Encarnacion], you don’t want to see Edwin hurt [oblique], Tauchman is hurt, so I think [Stanton] will just slide right into that left-field role for us, mix in a DH a little bit,’’ Judge told The Post.

“But once we get into the postseason, he’ll be out there in the outfield. The biggest thing he has to realize is that these last 12 games are important, but what is more important to us and the team is him getting ready for the postseason.

“Say you struggle the first couple of games, ‘Hey, forget about it, you just keep working on what you need to work on.’ We’ll still be fighting for the best record in baseball, and he is going to come out here to win every game, but don’t get frustrated if he is not getting hits. Make sure of your preparation. You are seeing the right balls, you are swinging at the right pitches.’’

Judge got to the heart of the matter.

“He is a big piece,’’ Judge said. “I know a lot of people might have said, ‘Why bring him in now? He’s missing the year, you got a good thing going on.’ But he is an MVP, he knows what to do. He’s come back from injuries before, he knows how to come back.

“We’ll be adding another guy who can leave the park at any time. Just do your job. And he has been around the team all year, it is not like he has been gone for six months and all of a sudden he is a new player coming in, he’s been around the team, vibing with us, hanging with us. There will be no letdown. I know that. It will be a big relief for a lot of guys. ‘We got Stanton now, too.’ It makes that one through nine even tougher.’’

That is the attitude in the clubhouse, a major reinforcement arriving for the postseason.

“It’s exciting,’’ Aaron Boone said of getting the injured stars back. “We’re talking about a lot of impact players. A lot of impact guys that can impact us potentially in the postseason.

“Some big names we are talking about that we know the kind of difference makers they can be. It’s exciting getting them back and hopefully getting them to a point to where not only are they feeling confident but we are all feeling confident in the kind of impact they can have on us.’’

Boone said it is his “hope’’ Stanton will be an everyday player when he does return this week at Yankee Stadium.

“I’ve texted with him and I think really over the last couple of three weeks he is starting to feel good about the progress he is making and kind of getting to that end game of being ready to play,’’ Boone said.

The Yankees have 12 games to get it perfect. Then it is go time.