Beltran's bone spur in his right elbow has forced the right fielder to the disabled list as he waits for a cortisone shot and pills to kick in.
It usually takes a few days before the medicine takes its full effect. If it doesn't ease the pain in Beltran's elbow, he could face surgery. Beltran estimated an operation would cost him six to eight weeks.
"I'm getting better but not to the point I'm capable of swinging a bat," Beltran said.
Reserve outfielder Ichiro Suzuki, has been out with a back issue, but is not expected to go on the disabled list. If healthy, Ichiro likely will play more in the outfield, joining Jacoby Ellsbury and Brett Gardner. Alfonso Soriano will play some outfield and DH.
The Yankees signed Beltran to a three-year, $45 million contract this offseason. He is hitting .234 with five homers and 15 RBIs.
Beltran originally felt the pain in the elbow taking swings in the batting cage during Monday night's Subway Series game against the Mets in the Bronx, where he served as the Yankees' DH.
Beltran's spot on the 25-man roster was taken by Thursday's rookie starter, Chase Whitley.