OAKLAND, Calif. -- At one point late in Friday night's game, Josh Reddick hustled up to the clubhouse for a quick protein bar when he saw that Coco Crisp was hitting again. Reddick ran back down to the field before his turn came up again.

The Oakland Athletics experienced one of those rare offensive nights when nearly everything that could go right did. For everybody, too.

Brandon Moss had career highs of four hits, four RBI and four runs, Reddick hit his first career grand slam, and the surging, surprising A's routed the Boston Red Sox 20-2 to match their best winning streak of the season at seven.

"It's fun, everybody's running to the bat rack ready to bat," Reddick said. "You can't wait to get in the batter's box."

What a way to head into the season's final month. And what a thump for Boston the week it unloaded its roster.

Josh Donaldson homered for the third straight game with a two-run shot and Moss also had a two-run drive to go with two RBI doubles to help back Brandon McCarthy (8-5) with a season high in runs.

Reddick connected for his 28th homer in the seventh off Mark Melancon as the A's scored their most runs since a 23-2 win over Texas on Sept. 30, 2000. They handed the Red Sox their most lopsided loss since a 22-1 defeat to the Yankees on June 19, 2000.

The A's had a season-best 19 hits and scored 20 runs for the fourth time in Oakland history, while Boston allowed 20 for the first time since Aug. 21, 2009, against the Yankees. Oakland has won six straight over Boston -- the Red Sox's longest skid in the series since also dropping six straight in 1969.

"It wasn't any fun for anyone, that's for sure, except for the guys on the other side," Red Sox manager Bobby Valentine said.

George Kottaras had his first career two-homer game with a two-run drive and a solo shot on the way to a career-best five RBI for Oakland (74-57), which matched its win total from 2011 and wrapped up an 18-10 August. The A's hit a season-high five home runs a day after getting four at Cleveland.

Oakland's nine-run seventh inning was the club's biggest since a nine-run frame last July 27 against Tampa Bay.

Jonny Gomes drove in two runs on a night he helped honor the Little League World Series players from his hometown of Petaluma in Northern California's wine country.

"I don't know that I can ask for much more than 20 runs," A's manager Bob Melvin said.

Donaldson added his third RBI on an error in the seventh, but was lifted for pinch-runner Adam Rosales at third after feeling some tightness in his right hip flexor. He hoped to play Saturday.

McCarthy won consecutive starts for the first time since June, and it was good timing with the A's leading Baltimore by a game in the AL wild-card race heading into the final month. The right-hander missed all of July while on the disabled list for a second time this year nursing a strained throwing shoulder.

Donaldson connected for his fifth home run of the year in Oakland's four-run second against Aaron Cook (3-8), who also surrendered an RBI double to Moss and a run-scoring single by Gomes during the inning.

Cook went just 2 2/3 innings to match his shortest outing of the season. The right-hander was tagged for six runs and seven hits and fell to 0-3 over his last four starts.

Jarrod Saltalamacchia hit a two-out solo homer in the fourth for Boston, which lost its fourth straight game after being swept by the Angels in Los Angeles.

"Nothing to talk about. The score was 20-2!" second baseman Dustin Pedroia said.

Oakland returned from a 6-1 road trip to notch another impressive win on a night when the Petaluma Little Leaguers, third in the Little League World Series, played catch with the A's on the field before the game and were honored in a pregame ceremony.

While Oakland is expected to activate third Brandon Inge from the disabled list when rosters expand Saturday, Melvin will have a tough time taking Donaldson's hot bat out of the lineup -- as long as he is still healthy. Inge has been on the DL since Aug. 12 with a sprained right shoulder.

Second baseman Cliff Pennington made a great catch on a shallow fly ball by Jacoby Ellsbury to end the third, sprinting backward to complete the play, then hit an RBI double in the seventh. Stephen Drew also got into the seventh-inning fun with an RBI single. Everybody on the Oakland roster scored.

Pedroia extended his hitting streak to 11 games with a first-inning single for the new-look Red Sox, who last week sent a handful of former stars to Southern California to join the Los Angeles Dodgers as they try to make a push in the NL West against the first-place San Francisco Giants.

Notes

• Red Sox DH David Ortiz could rejoin the club at Seattle early next week or once the team gets back home after he received an injection in his strained right Achilles that landed him on the DL this past Monday.
• A.J. Griffin (3-0) will be recalled by Oakland to start Saturday as LHP Brett Anderson gets an extra day of rest before pitching Sunday.
• Oakland leads the season series 6-1 and has won more than five games in a single year against the Red Sox for the first time since going 7-3 in 2006, the A's last year in the playoffs.
• Oakland recalled RHP Pedro Figueroa from Triple-A Sacramento and optioned RHP Jim Miller to Class-A Stockton. With Sacramento in the playoffs and Stockton's season about to end, Miller is eligible to rejoin the A's Tuesday and that's the plan.
• The 18 runs allowed by Boston matched its most of 2012, April 17 against Texas. The Red Sox gave up nine runs in an inning for the first time since Sept. 27, 2006, against the Rays.