AP Baseball Writer

NEW YORK (AP) _ Yankees pitcher Masahiro Tanaka is going to be out at least a month because of tendinitis in his right wrist and a mild right forearm strain.

General manager Brian Cashman said Tuesday night during New York’s 4-2 win over Tampa Bay that tests showed no change in Tanaka’s partially torn elbow ligament. The Japanese star last year chose not to have Tommy John surgery and missed 2 1/2 months rehabbing the injury.

“We want to make sure this doesn’t lead to the more horrific problems that we’re all trying to avoid,” Cashman said.

Tanaka is 2-1 with a 3.22 ERA and was superb in his last two starts, alleviating fear about the elbow. But he complained of pain in the side of his wrist Tuesday when he arrived at Yankee Stadium _ even though pitching coach Larry Rothschild said Tanaka’s bullpen session between starts was “fantastic,” according to Cashman.

“I woke up the next morning and I felt it a little bit in the wrist area, but I thought it would be fine,” Tanaka said through a translator. “I went out and played light catch on that day, which was yesterday. I woke up this morning and felt it a little more than the day before, so that’s why I went over to Steve (Donohue) our trainer, and told him about it.”

Tanaka had MRIs on both the wrist and elbow, and the test on the wrist showed no issues, but it hurt to the touch. While the elbow was clear, Cashman said Yankees team physician Dr. Christopher Ahmad identified a “very mild” forearm strain.

“I was shocked,” manager Joe Girardi said when he learned of Tanaka’s injury, which came on the pitcher’s bobblehead night.

The Yankees immediately placed Tanaka on the 15-day disabled list, and he won’t throw at all for seven to 10 days.

Cashman acknowledged the forearm protects the elbow and that this “could be” a precursor to reconstructive elbow surgery.

“It has nothing to do with my elbow,” Tanaka said. “That’s something that’s out of the question for me.”

Michael Pineda will start in Tanaka’s place Wednesday against Tampa Bay on regular rest. Tanaka was originally slated to pitch Tuesday night but was bumped back a day for extra rest.

Chase Whitley pitched well in a spot start Tuesday and should get at least one more.

“Right now he’s in our rotation,” Girardi said.

The Yankees signed Tanaka to a seven-year, $155 million contract before last season after he went 24-0 with a 1.27 ERA for the Rakuten Golden Eagles in Japan.

He got off to a superb start with New York and was selected to the All-Star team as a rookie. He was shut down in July because of the elbow injury and returned in September to make two starts. Tanaka finished the year 13-5 with a 2.77 ERA.

Some attributed Tanaka’s injury last year to throwing a lot of split-finger fastballs, a pitch that puts a lot of strain on the arm, and the one fewer day of rest between starts than he was accustomed to in Japan.

But he dismissed those ideas Tuesday.

“No, I don’t think it has (anything) to do with that,” Tanaka said. “I don’t think it has anything to do with me throwing a split-finger.”