Suspect curveball likely holding up Ivan Nova’s return

Ivan Nova Photo: APMIAMI — Having decided Ivan Nova requires another minor league rehab start, the Yankees don’t immediately need to drop a starter from the rotation.

Nova, who has made two rehab outings in the late stages of his comeback from Tommy John surgery, will get an extra day between starts and pitch on Friday night. As of early Monday night, Joe Girardi didn’t know whom Nova would pitch for.

“We just feel that he is finished off [the rehab]. It’s not something easy to make an adjustment if we said, ‘We wished we would have had one more start,’ ” Girardi said before the Yankees fell 2-1 to the Marlins. “We talked about it for a couple of days and it would be better to know he is…