OAKLAND, Calif. -- Jason Giambi's legs have been bothering him for months. His extended slump has affected the slugger, too.
The Oakland Athletics placed their first baseman and designated hitter on the 15-day disabled list Monday with a strained right quadriceps muscle, a nagging injury that has been just part of the problem.
The A's said the injury wasn't considered career-threatening, but couldn't provide a timeline for when Giambi might be ready to return. The 38-year-old Giambi has been dealing with sore legs for much of the season, with his hamstrings also causing him trouble.
He won't make the next road trip, which begins in New York on Thursday with four games against his old team at new Yankee Stadium.
General manager Billy Beane said the A's needed a healthy body given the fact Giambi couldn't play as regularly.
"It got to a point it was difficult to consistently make a lineup with him," Beane said.
Manager Bob Geren said there wasn't one incident that he knew of in which Giambi was hurt, but the first baseman slid into the bag while on defense Sunday to make a play during Brett Anderson's bid at a perfect game. Giambi was removed from the team's 10-inning, 1-0 loss to the Los Angeles Angels in the top of the ninth and replaced by Bobby Crosby. Geren said Monday that move was intended to get fresh legs in the game.
"I'm not aware of a specific play," Geren said. "He's given me his all. ... It's just something we're going to try to get Jason healthy. It's something that's been coming on."
Geren acknowledged the mental break also could be good for Giambi, who made a brief stop at the ballpark Monday but wasn't around to talk to reporters.
"Sometimes that can be beneficial if you want to look at a positive," Geren said.
Giambi, in his first season back with his original team following seven years with the New York Yankees, began the day Monday with the lowest batting average in the majors among regulars at .193. He is 7 for 57 over his last 19 games, and has 11 homers and 40 RBIs in 83 games on the year.
That's a far cry from the player he was for the A's during his first stint with the club from 1995-2001. He won the AL MVP in 2000.
"Knowing Jason as long as I have, he expects a lot out of himself," Beane said. "He takes his performances to heart and takes them personally. He feels a responsibility not just to himself but to everybody around him. He's disappointed in the first half he had and feels like he's capable of more."
Geren said the club could use Giambi primarily as a designated hitter upon his return because "sometimes it's easier on a lot of people's bodies."
To replace Giambi, the A's recalled first baseman Daric Barton from Triple-A Sacramento and put him in the starting lineup for the opener of a three-game series against the Minnesota Twins. This is Barton's second stint with the A's after he batted .118 with one RBI in 12 games in June.
But Barton has provided plenty of signs he's coming around. He was hitting .321 with six homers and 16 RBIs with a .463 on-base percentage in 15 games for the River Cats since being sent down June 28. Beane acknowledged this could be a key evaluation period of Barton by the club.
"He started off very slowly in Sacramento," Beane said. "But since his first couple of weeks he's been playing great."
The A's have used the disabled list 13 times this season. They set an Oakland record in 2008 with 25 DL stints and have placed 60 players on the disabled list since the start of the 2007 season.