Manager Joe Girardi announced the decision after New York beat the Blue Jays 5-2 for their fourth straight win. The move is retroactive to Aug. 9.
The Yankees have also agreed to a contract with free agent Derek Lowe and are planning to finalize the deal and activate him Monday. The right-hander, recently cut by the Cleveland Indians, likely will pitch out of the bullpen. David Phelps is a candidate to take Sabathia's spot in the rotation.
Girardi said Sabathia, the 2007 AL Cy Young award winner, felt stiff two days after his Aug. 3 start against Seattle, but an MRI showed nothing. Sabathia felt stiff again after pitching at Detroit on Aug. 8. He threw on flat ground Friday rather than throwing his regular bullpen session and continued to experience mild discomfort.
"It's not any worse than it was after the first start, but our concern is it didn't go away," Girardi said.
"As far as the concern, it's pretty low level, because it's not like it got any worse," Girardi added. "He wants to pitch on Monday, which I'm not surprised [at] because he said he dealt with it before. We just decided, let's try to get it cleaned up now."
Girardi said Sabathia is scheduled to see a doctor when the Yankees return home Monday and could receive a cortisone injection. Sabathia has been having treatment since the pain first arose.
The Yankees debated skipping Sabathia for one start but decided an extended break was the wiser plan.
Either way, Girardi stressed that Sabathia's condition was not considered especially serious.
"If it's October, I'm not sure what we do," Girardi said. "I think he makes his start."
Girardi said the plan is to activate Sabathia when his DL stint expires and have him return to the rotation Aug. 24 at Cleveland, the city where his major league career began.
Sabathia was pulled after 94 pitches in his win at Detroit on Wednesday, and Girardi acknowledged he was being "a little bit cautious" with his tender ace.
Sabathia, 12-3 with a 3.56 ERA, missed 18 games earlier this season with a strained left groin.
"We're going to have to deal with it, that's the bottom line," Girardi said. "We don't want to, but we need to have him healthy. If we're going to continue to move on, we need to have him healthy."
Sabathia was spotted in the clubhouse with an ice pack on his elbow before Saturday's game. Asked about it, Girardi that Sabathia was fine, and that the ice pack was "preventive."
Sabathia did not speak to reporters Saturday but is expected to address his situation before Sunday's series finale against the Blue Jays.
Lowe (8-10) was designated for assignment by Cleveland on Aug. 2 after losing four straight. He had an 8.80 ERA over his last 12 starts for the Indians.
The 39-year-old began the season 6-1 with a 2.05 ERA but finished his stint with the Indians in a 2-9 slide, with his ERA ballooning to 5.52.
The 16-year veteran is 174-156 with 85 saves in his career with Cleveland, Atlanta, the Los Angeles Dodgers and Boston. He is in the final year of a four-year, $60 million contract.