"I thought he'd be ready. He's not ready, so we'll have to make an evaluation," Yankees manager Joe Girardi said. "We'll see what he can do today and see where we're at."
Nunez said that there are no tests planned, but he has told head athletic trainer Steve Donohue that he still feels the rib cage discomfort when he tries to play in the field.
"I feel a little something over there," Nunez said. "They shut me down. They don't want it to be worse."
Accelerating the Yankees' decision is the single-admission doubleheader they will play on Monday against the Indians in Cleveland, and Girardi said he will need to summon another infielder if Nunez isn't able to play by then.
The Yankees can also add a 26th man for Monday's doubleheader, and Girardi said that the plan is to use that rule to call up an extra pitcher. Girardi said he and general manager Brian Cashman expected to have a final decision on Nunez by Monday.
"I would think so," Girardi said. "I talked to Cash a little bit about it today and I'll probably talk to him about it after the game and see where we're at."
Two possible replacements for Nunez on the active roster are Corban Joseph and Ronnier Mustelier, both of whom are playing at Triple-A Scranton/Wilkes-Barre. Joseph was with the big league club earlier this season but did not appear in a game, while Mustelier's live bat gave him a chance to make the team in Spring Training before he sustained a knee injury running into a railing.
The New York Daily News reported on Saturday that the Yankees are planning to call up 25-year-old infielder David Adams next week, but he is not eligible to join the big league club until Wednesday because he was released and then re-signed a Minor League deal with the Yankees in April.
Bryan Hoch is a reporter for MLB.com. Follow him on Twitter @bryanhoch and read his MLBlog, Bombers Beat. This story was not subject to the approval of Major League Baseball or its clubs.