BOSTON (AP) -- Oakland manager Art Howe would trade it all -- the 13 runs, the 11 hits, and even the victory -- to get his first baseman back.

Eric Chavez hit a grand slam as the Athletics scored six runs in the first inning and kept on scoring Friday night to beat the Boston Red Sox 13-6.

	Jason Giambi (16) has a hyperextended right knee and will sit out Saturday's game at Boston.

But the A's mood soured when Jason Giambi pulled up lame in the seventh inning with injuries to his right knee and hamstring.

"It's a bittersweet victory because of that," Howe said. "It's one of the keys to our success, to stay healthy. But that's what you've got bench players for."

Kevin Appier (2-1) allowed three earned runs and eight hits in six innings, striking out six to win his second consecutive start. Frank Menechino also homered in the first inning for the A's.

Giambi was 1-for-3 with two walks and a three-run homer -- his fifth of the season, second in the AL.

In the seventh inning, he hit a ground ball to the second baseman in the hole behind first base. He might have been able to beat it out, but he pulled up a few steps before the bag.

"I don't know how I came down on it or when I did it. It just locked up on me," he said. "We'll see how it comes back tomorrow. Hopefully, it won't be too long."

Giambi was diagnosed with a hyperextended right knee and also a hamstring injury. Doctors won't know how severe the latter is until they examine him Saturday, after the swelling has subsided.

"I'll give him (Saturday) off for sure," Howe said. "That will give the trainers a chance to diagnose it."

Brian Rose (0-2) retired only two batters and walked four, giving up a two-run homer to Menechino and then walking the bases full before giving up Chavez' third home run of the season.

"I let my team down today," Rose said after the Red Sox lost for the first time in four home games. "I let the fans down because we seemed to have something going the last couple of days."

Menechino also doubled and scored in the second to make it 7-0.

The Red Sox cut the deficit to five runs on Nomar Garciaparra's two-run single in the third. Wilton Veras singled to lead off the fifth, took third on Jose Offerman's single and scored on Trot Nixon's sacrifice fly.

Offerman took second on Brian Daubach's single, and Garciaparra hit a grounder to short, forcing Daubach. But Daubach went hard into Menechino at second base, forcing him to throw wide on his attempt for a double play and allowing Offerman to score to make it 7-4.

Giambi hit a three-run homer in the sixth, and Oakland scored three more in the seventh to make it 13-4. Garciaparra added another RBI single in the seventh to make it 13-5.

Game notes
It was Oakland's first road game of the season. ... Menechino has reached base safely in nine of Oakland's first 10 games. ... Appier's last shutout was at Fenway Park on May 5, 1997, while with the Royals. ... Red Sox 3B Gary Gaetti retired before the game and was replaced on the roster with infielder Andy Sheets. Garciaparra had his first two-error game since Game 1 of the AL Championship Series last year against the New York Yankees. ... Chavez was 3-for-5 with a career-high five RBI.