Manager John Gibbons was asked if Donaldson would also sit out Sunday, which would give him a total of five days' rest because of two off-days, but he insisted that would not be the case.
"No, because I think we need him, but I think one more day will do him a world of good," Gibbons said. "Get him back, rested up and make sure that's good. That can nag and affect your swing, but we need him offensively. Every game is important."
Donaldson sustained the injury while grounding out during a 7-4 victory over the Yankees on Wednesday afternoon. He dealt with a similar issue earlier this year but only missed one game. He is batting .289 with 28 home runs and 80 RBIs in 119 games this season.
The news was more encouraging for Troy Tulowitzki, who made his return to the lineup after he sat out Friday because of a sore calf muscle on his right leg. Tulowitzki got the start at designated hitter and is expected to return to shortstop on Sunday afternoon.
Pillar starts rehab
Blue Jays center fielder Kevin Pillar officially began his rehab assignment with Class A Advanced Dunedin on Saturday afternoon. He went 4-for-5 with a run scored and two RBIs in his debut.
Pillar is on the 15-day disabled list with a sprained left thumb. He is expected to return when eligible for Tuesday's series opener against the Angels at Rogers Centre. Pillar is expected to play one more game for Dunedin before making the trip north.
Gregor Chisholm has covered the Blue Jays for MLB.com since 2011. Follow him on Twitter @gregorMLB and Facebook, and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.