CLEVELAND -- For a team leading the wildcard race, the Oakland A's couldn't have hand-picked a better opponent to play in the four-game series that ended Thursday.
The A's, who have won six games in a row, and 12 of their last 14, took advantage of the reeling Cleveland Indians, belting four home runs and beating Cleveland 12-7. Oakland is 9-2 vs. Cleveland this year.
With the victory the A's maintained their one-game lead over Baltimore in the wildcard race while completing their first four-game sweep of the Indians in Cleveland since 2002.
The A's, who got home runs from Coco Crisp, Cliff Pennington, Josh Reddick and Josh Donaldson, took control of the game with a 10-run outburst in the middle innings.
"We played against a team we really needed to take a series from," said Reddick. "We had a great opportunity to move up in the standings against a team we've played well against all year, and we did just that."
For the Indians, it was their fourth loss in a row and their 14th loss in their last 15 games. Since July 26 their record is 5-27.
Indians manager Manny Acta, who had the team in first place in the AL Central for 40 days in earlier in the season, said the team's rapid collapse is uncharted waters for him. The Indians are a major league-worst 5-23 in the month of August.
"I've never been through a month like this anywhere in the minors, in winter ball, or in the majors as a coach or manager," said Acta.
A's starter Jarrod Parker, handed an early 6-1 lead, gave up five runs in five innings, but that was good enough for the win, improving his record to 9-7. Cleveland starter Justin Masterson (10-12) only lasted four innings and was charged with eight runs on eight hits.
"It's embarrassing to get that kind of lead and not work efficiently and get back in that dugout," said Parker, who was removed from the game after giving up two hits and a walk to the first three batters in the sixth inning.
Cleveland took an early 1-0 lead on a home run by leadoff hitter Jason Kipnis in the first, but it was all Oakland after that.
Crisp hit a solo home run with two outs in the third inning, and the A's really went to work on Masterson in the next two innings.
In the top of the fourth, Yoenis Cespedes singled and Seth Smith and Josh Donaldson walked to load the bases with two outs.
George Kottaras slammed a three-run double into the right-center field gap, and Pennington followed with a two-run homer to extend the Oakland lead to 6-1.
"Jason just didn't have it today," said Acta of Masterson. "He was falling behind in the count a lot and the bottom of their order really did a lot of damage."
Reddick added a two-run homer in the fifth inning to make it 8-2. Cleveland rallied briefly with a three-run sixth inning that included a two-out two-run single by Shin-Soo Choo But the A's continued their offensive assault against the Cleveland bullpen as Oakland improved to 36-15 since July 1, the best record in the majors in that span.
Notes: Indians pitching coach Ruben Niebla, was thrown out of the game by home plate umpire Paul Emmel in the seventh inning, when Niebla made a visit to the mound. Indians reliever Tony Sipp walked four batters in the inning. "We walked four guys in the inning. You can't blame the umpire. He can't miss 16 pitches," said Acta. ... Indians right-hander Roberto Hernandez, who was forced out of his last start with a sprained right ankle, has had no issues with the ankle in his between-starts work and will make his next scheduled start Saturday vs. Texas. ... Kipnis' leadoff home run in the first inning was the Indians' eighth of the season, equaling the team record. Shin-Soo Choo has hit five, Kipnis two and Jason Donald one. The Indians also had eight first inning leadoff home runs in 2008. ... Oakland pitchers walked seven in the game. That snapped a streak of 25 consecutive games in which A's pitchers had walked two batters or fewer, the longest such streak in Oakland history. ... A's third baseman Josh Donaldson, who homered in the ninth inning, also had a home run in Wednesday's game. It's the first time in Donaldson's career he has hit home runs in consecutive games.