OAKLAND -- Josh Donaldson is dealing with back stiffness and was out of the A's lineup for a second straight day on Thursday.
"That was the reason he wasn't in there yesterday," manager Bob Melvin said before Thursday's series opener against the Blue Jays. "We'll give him another day here, see how he feels tomorrow."
Donaldson took regular batting practice on Thursday, but did not field any ground balls. Melvin wanted to see how the third baseman felt after swinging the bat to determine whether he might be available off the bench.
Thursday marked just the fifth game this season that Donaldson has not started. He has 18 home runs and 61 RBIs and looks poised to start his first All-Star Game, though his average has dipped from .284 to .245 since June 1.
O'Flaherty returns to big leagues as A's DFA Francis
OAKLAND -- The A's reinstated left-hander Eric O'Flaherty from the 60-day disabled list on Thursday afternoon and designated lefty Jeff Francis for assignment.
O'Flaherty underwent Tommy John surgery on his pitching elbow in May 2013, and the A's signed him to a two-year, $7 million deal in January. He made eight appearances during a Minor League rehab assignment that began on June 6, posting a 3.86 ERA while holding opponents to a .188 batting average.
The 29-year-old's seventh and final appearance with Triple-A Sacramento came on Tuesday, when he threw one scoreless inning.
"I couldn't sleep last night, for sure," O'Flaherty said Thursday. "It's cool to join a team this good and a bullpen this deep where there's not going to be too much pressure on me to shoulder too much of a load. I can just kind of get in where I fit in and help any way I can."
Manager Bob Melvin would ideally like to start by using O'Flaherty in a few low-leverage situations.
"I'd like to get him in some games before we get him pitching in the seventh or eighth inning with two on," Melvin said. "In a perfect world, you'd like to get him in a couple of settings where it's a bit of a soft landing, but we'll see if that transpires."
Over the past five seasons, O'Flaherty has been one of the premier left-handed relievers in baseball, compiling a 1.99 ERA in 249 1/3 frames with Atlanta. Lefties have hit .200 against him in his career.
"His four- and two-seam [fastballs], he gets a lot of late movement on it," said Melvin. "He's got a really good slider that he can throw down and in to a righty, away from a lefty. He can do it all."
O'Flaherty has yet to pitch on consecutive days, but he believes that step will come shortly. His rehab process went smoothly, with no major setbacks, and he said his velocity is similar to before the surgery.
"Maybe not topping out the same, but I usually don't get my velocity until about this time of year anyway," he said. "Getting a late start, hopefully there's a little more in the tank, but I can definitely pitch where I'm at."
Francis was claimed off waivers by Oakland on May 18 and went 0-1 with a 6.08 ERA in nine relief appearances. He picked up his first career save on Saturday.
• Yoenis Cespedes was back in left field on Thursday, his left hamstring feeling better after he injured it on Monday in Detroit. Cespedes took Tuesday off before playing Wednesday as the designated hitter.
Melvin noted that Cespedes has, to some extent, learned to "play around" the hamstring issue, which has lingered over the past few years.
• Left-hander Drew Pomeranz (fractured right hand) threw another bullpen session Thursday with his glove on, but he is still unable to receive throws. Pomeranz went on the 15-day disabled list on June 17.
Aaron Leibowitz is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.