MLB

Yankees, Mets set for first pitch

Things can change a lot in a year.

Last year it was the Mets carrying around World Series expectations, and the Yankees were the ones trying to figure out how to survive the first month of the season without an injured superstar.

The Mets will be without Carlos Beltran until the middle of May (knee), won’t have Jose Reyes (thyroid) until at least the fifth game of the season, will be without Daniel Murphy (right knee) for 2-6 weeks and no one knows what to expect from four-fifths of their rotation.

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“The Mets being a huge disappointment last season, it really is important for their own psyche to get off to a good start,” said YES and MLB Network analyst Al Leiter, who pitched with both New York teams.

“They need guys to step up and see their potential. If they fall behind it could be a real long summer.”

The Mets open their season with a six-game homestand against the Marlins and Nationals before heading west for series against the Rockies and Cardinals, two playoff teams from last year.

While the Mets will be trying simply to keep pace with the Phillies in the NL East, the Yankees will be trying to build on the success of last year’s World Series when they open their season against the Red Sox on Sunday night. The Yankees will start the year with a healthy Alex Rodriguez, after the steroid-scandal scarred superstar missed the first month of last season with a torn labrum in his right hip.

“The awkwardness of all his teammates having to listen to him talk about his [performance-enhancing drugs], it just didn’t feel like the Yankees,” Leiter said. “It just seems better, calmer and back to business as usual for the Yankees. There wasn’t a whole lot of tweaking that had to be done this offseason, so they will be right there.”

The Mets are hoping to be right there, too. But ESPN “Baseball Tonight” analyst Aaron Boone preaches patience until the Mets have Beltran back and the team is at full strength.

“The Mets should be a better club a month into the season,” said Boone, who retired last month. “When they get Beltran back and Reyes is 100 percent, they should be fine. But there’s no more pressure on the Mets to get off to a good start than any other team.”

And the Red Sox know better than most that early-season success does not guarantee anything in October. In early June, Boston was 9-0 against the Yankees and had built a 9 1/2-game gulf between them and their rivals. The Yankees finished the season 9-1 against the Red Sox on their way to a championship.

“Anytime it’s Red Sox-Yankees, you’d be lying you said you weren’t wired up,” said Boone, whose ALCS-winning home run for the Yankees in 2003 is one of most memorable moments the two teams have produced.

“One of the one things I learned while playing in this rivalry was not to believe so much in momentum in baseball,” Boone said. “It seemed like every time we beat them, they would beat us. . . . It’s so early in the season, so much can happen and the players know that.”

justin.terranova@nypost.com