Tanaka to throw in 1st step back

BOSTON — Masahiro Tanaka will test his right elbow Monday by playing catch at Yankee Stadium, according to Brian Cashman.

“Yes,’’ the general manager answered when asked if Tanaka was scheduled to throw Monday.

If Tanaka, who has a small tear in his ulnar collateral ligament, comes through the exercise without a problem, the rehab program will continue. However, if he experiences a problem it could lead to Tommy John surgery, a procedure that takes 12to18 months to recover from.

Tanaka, who hasn’t pitched since July 8 in Cleveland, received a plateletrich plasma injection July 14 and has been resting his elbow since.

Tanaka was examined Friday by Chris Ahmad, the Yankees’ physician, and Cashman said, “Every day that there isn’t a problem is a good day.’’

When Tanaka went down Cashman said September was a possible return date.

“We will see what everyone wants to do with him,’’ Joe Girardi said before the Yankees’ 87 win over the Red Sox. “We said three weeks was the mark and the doctor said he feels good and we will talk and decide what we are going to do.’’

If Tanaka passes Monday’s test the Yankees manager said he wasn’t sure the $175 million investment would be starting from ground zero.

“I am not sure it’s starting all over because he has been built up, but it’s 60 feet, 90 feet, 120, flat ground, bullpen and rehab game,’’ Girardi said.

➤ Girardi was more encouraged by how Michael Pineda came out of Sunday’s minor league rehab game than his numbers, which were solid.

“He felt good, which obviously is very important,’’ Girardi said of the righthander who threw 3 ¹/₃ shutout innings for TripleA Scranton/ WilkesBarre against Syracuse, allowing three hits, a walk and whiffing four. “He will make his next start Friday, not sure where. He threw the ball pretty well and [we’re] pleased with the progress he is making.’’

Pineda threw 58 pitches and Friday will be stretched to 75. After that the next milestone is 90, and the hope is Pineda, who hasn’t pitched since April 23, will be able to rejoin the rotation.

➤ Rusney Castillo, a Cuban defector who is clear to sign with any MLB club as a free agent, will conduct a private workout for the Yankees on Friday in Tampa.