He’s just arrived from Toronto, but it’s already a rap for Marcus Stroman.

The Mets’ new pitcher, 28, has a secret life as an aspiring hip-hop artist. He’s co-starred in a video for and dropped lyrics on songs by his former Duke teammate, rapper Mike Seander, who has performed as Mike Stud and now just goes by Mike.

“It’s clean, positive and aligned with his brand,” Seander, 30, told The Post of the pro athlete’s hip-hop side hustle. “Marcus always wanted to be a musician.”

Stroman, who is 5-foot-8, has even joined Seander on tour, rapping onstage in cities including Toronto and Tampa about being undersized and captivating a game-day crowd.

“When I go on tour, I bully him into performing,” Seander said. “He talks about how he gets more nervous going in front of 600 people with a microphone in his hand versus 40,000 with a baseball in his hand. The nervousness makes him feel alive.”

The two met at Duke in 2009. Seander was recovering from Tommy John surgery and started rapping during his time off from the baseball team.

When his new career started picking up steam thanks to Youtube, Stroman, a Medford, LI, native, became his sidekick while Mike recorded tracks.

Seander quit baseball after college while Stroman in 2012 became the first Duke player ever to be selected in the first round of the Major League Baseball draft.

“[Our careers] have obviously evolved but the music is one thing that keeps us really close,” Seander said.

The Mets did not return calls for comment.

In 2016, the pair traded places in a video for the song “These Days” — with Stroman channeling Seander living the Los Angeles fast life and Seander on a baseball diamond.

“We’re living our dreams vicariously through each other in the video,” said Seander.

Stroman, a right-handed hurler, also has cameos on Seander’s songs “Shine” and “Take It How you Wanna,” a remix of “These Days.”

Athletes Shaquille O’Neal, Kobe Bryant, Allen Iverson and new Jet Le’Veon Bell have all tried their hand at the rap game.

“I think Le’Veon is one of the best. But Marcus is better,” said ­Seander.

Seander says Stroman will settle into the Mets organization before he gets back in the studio, but is confident his sidekick can excel at both.

“He is definitely breaking stereotypes,” Seander said.