"We were just bad all the way around," manager Bob Melvin said. "We're not proud of the way we played.
"They're playing great, can't do anything wrong, and we're struggling. That's what happened. What happened last night should shouldn't affect today. They just beat us."
Josh Donaldson hit his fourth home run of the season for the A's. It came on a 2-2 count in the sixth inning.
Oakland starter Bartolo Colon made starts regularly at Progressive Field as a member of the Indians from 1997 to the middle of the 2002 season. Considering his 75-45 record with the Tribe, it seems safe to say that he typically had more fun here during his younger years than he did on Thursday afternoon.
Colon (3-2) was shelled for six runs in his visit to the old stomping grounds. In just four innings of work, the right-hander allowed eight hits, and all six of his runs were earned. He notched four strikeouts without a walk. The start was his shortest of the year, and he gave up more earned runs than he had in any other outing this season.
"He didn't look awful," Melvin said. "Velocity was there. The balls he got in the middle of the plate, they hit. And they did it the whole series. Sometimes the other team just beats you. Today that was probably the case. We had a couple of chances early on. We didn't come through. And every time they had an opportunity, they did."
Half of Colon's runs came via a two-run dinger by Jason Kipnis and a solo shot by Nick Swisher. The veteran also surrendered a run-scoring double to Yan Gomes, who reached third on an error in right by Brandon Moss and scored on a single by Drew Stubbs. Later, Kipnis plated Stubbs with a sacrifice fly.
"I feel good," Colon said through a translator. "The only problem was the Cleveland team right now is hot. I tried to do the best I could."
Indians manager Terry Francona was impressed with Colon, but not as impressed as he was with his own guys.
"We stayed on Colon," Francona said. "He's got that terrific two-seamer that you're just dying and rolling over into a double play. We didn't. We stayed in the middle of the field, and we barreled up a lot of balls and we stayed at him."
Evan Scribner relieved Colon after four innings. He allowed a leadoff double to Asdrubal Cabrera, who crossed the plate on a Jason Giambi single. Soon after, Mark Reynolds brought Giambi home with his league-leading 11th home run of the season.
In the four-game series, the Indians belted nine home runs compared to just two for the A's. Well, two if you don't count Adam Rosales' controversial ninth-inning drive from Wednesday.
On top of it all, Oakland committed five errors in the final three games of the series.
"At the very least, when you're not hitting and you're getting beat, you want to play clean games defensively, and we didn't do it," Melvin said.
Donaldson's homer came in the sixth, with his team already trailing by nine runs. It was the only hiccup for Indians starter Scott Kazmir. Otherwise, Kazmir (2-1) was fairly dominant, going six innings and striking out 10 batters.
The A's added a single run with Tribe reliever Matt Albers in the game. Rosales led off the eighth with a walk, and Eric Sogard singled him home. Cody Allen replaced Albers, who left with the bases loaded and nobody out. Allen struck out the next two hitters and induced a weak groundout from Daric Barton to escape the jam.
The A's were last swept on April 17-19 in Tampa Bay. The last time they dropped each contest in a four-game set was during a road series against the Texas Rangers on July 7-10, 2011.
"We just had a really bad series," Melvin said, "and that's the way you get beat four games in a row."