ST. PETERSBURG, Fla. — New York Yankees ace Masahiro Tanaka will miss his scheduled start Monday at Toronto because of what Manager Joe Girardi called a slight lower right forearm strain.

Girardi announced Tanaka’s injury before Thursday night’s game at Tampa Bay. He said Tanaka won’t throw for five days but could start again before the regular season is scheduled to end Oct. 2.

“I feel like this is just a little nick,” Girardi said. “I’m not going to make too much out of this. I don’t think this is a huge thing. ”

Tanaka had an MRI exam Thursday, one day after he gained his 14th win despite allowing four homers in the third inning of a 11-5 win over the Rays.

Tanaka, who has won seven straight decisions, is 14-4 with an AL-leading 3.07 ERA.

METS: The already short-handed New York Mets saw their playoff chances dealt another significant blow when left-hander Steven Matz was scratched from his scheduled start Friday because of shoulder soreness.

Matz, 9-8 with a 3.40 ERA, hasn’t pitched since Aug. 14 because of tightness in his left shoulder but threw a bullpen session Wednesday and was set to return.

General Manager Sandy Alderson said the rookie’s shoulder again felt sore, one day after the bullpen session.

Said Alderson: “For the next several days, that shoulder issue has to resolve itself before we would consider pitching him again.”

Gabriel Ynoa, in line to follow Matz on Friday, will instead make his second major league start.

GIANTS: Pitcher Johnny Cueto had an MRI that confirmed a Grade 1 groin strain, which forced him out of his start in the sixth inning Tuesday. He’s questionable for his next start, although Manager Bruce Bochy hasn’t ruled him for the Giants’ next series.

DODGERS: Left-hander Scott Kazmir comes off the disabled list to start Friday against Colorado after missing nearly a month with neck inflammation.

He’s expected to throw about 90 pitches, but will be monitored.