Donaldson, who's filling in for the injured Brandon Inge, had a double and two RBIs and scored a run. Since being recalled from Sacramento, he's gone 7-for-14 and raised his average to .196.
"I just wanted to come up here and help these guys win," Donaldson said. " They've been doing a good job."
Donaldson hit .302 with eight home runs and 31 RBIs in 38 games with Sacramento after being sent down on June 21. He said the key to his recent hot streak with the A's is keeping the same approach he had with the River Cats.
"I'm not saying these guys are Triple-A pitchers by any means, but it's just having that mentality, that mindset of just believing in myself and allowing my ability to work," Donaldson said.
With the game tied, 4-4, in the bottom of the eighth, Chris Carter led off with a walk against reliever Joe Smith and moved to second on Brandon Moss' single. Pinch-hitter Josh Reddick loaded the bases with a soft single to left off reliever Vinnie Pestano, then Donaldson lined a single through the hole to left, scoring pinch-runner Adam Rosales.
"Since he's gotten here, he's swung the bat very well, playing with a lot of confidence," A's manager Bob Melvin said. "And we've seen that from several of our guys that have come up from Triple-A, including Chris Carter, Brandon Moss, Brandon Hicks, when he was here. So we're getting some contributions from everybody. And with Inge being down, we're getting some production on the offensive side from third. So I know he feels pretty good about that."
With one out, Cliff Pennington brought Moss home with a sacrifice fly, making it 6-4. Grant Balfour came on to pitch a perfect ninth for his 10th save.
A's left-hander Tommy Milone gave up a grand slam to Shelley Duncan in the fourth inning but avoided a fourth straight loss with a no-decision. He was pitching on 11 days' rest after struggling in his previous three starts. A's manager Bob Melvin had hoped the extra rest would help get Milone back on track. Other than one bad pitch, it did.
"Overall, it went all right," Milone said. "I felt good out there. Obviously the rest helped, but I think just that one pitch was really the only mistake I made all game."
Milone blanked Cleveland for the first three innings and in the fifth, but he allowed four runs in the fourth, all of them earned. Milone gave up a leadoff walk to Carlos Santana. Michael Brantley singled on a soft fly to left that A's left fielder Yoenis Cespedes lost in the lights.
Jason Donald singled to left, loading the bases and bringing Duncan to the plate. Duncan sent Milone's 3-2 pitch at the knees deep over the left-field wall for his first career grand slam and 11th home run of the season.
The A's rallied to score three runs in the bottom of the fourth. Carter led off with a sharp single to right off Indians right-hander Zach McAllister, and Moss walked. With one out, Donaldson doubled Carter home. Moss scored on Derek Norris' groundout to third. Pennington then singled to right, bringing Donaldson home.
"It's amazing," Milone said. "You give up four runs like that pretty quickly and we come back in the next half inning and score three just to come right back into the game. It just put a fire back in me to go back out there and keep it close."
The A's tied it, 4-4, with a run in the fifth. Cespedes ripped a one-out double to left, stole third and scored on Carter's sacrifice fly.
Milone, who threw 95 pitches, gave up six hits, walked one and struck out six over five innings before giving way to right-hander Pat Neshek.
"I thought he was sharper," Melvin said of Milone. "I thought he was better."
The same could be said for Donaldson since his return to the big leagues.