OAKLAND -- The Rangers went into the season with some concerns about Josh Hamilton's durability. They openly wondered how much rest he would need. They said that if he could post up for 140 games that would be terrific.

Turns out they can't get him out of the lineup. Hamilton was back in center field on Friday night and is the only Ranger who has started every game this season. That he is the Rangers' hottest hitter is a part of it, but his durability and endurance to this point in the season have been encouraging.

"I try to give him days off, but he comes into my office and says he doesn't need one," Rangers manager Ron Washington said. "We were struggling and he felt the team needed him in there, so his days off have been when he's the DH.

"As we get into the season, I'm going to have to give him days off. As soon as I get an opportunity, I'm going to give him a day off. He would have had two or three days off by now if he'd let me."

Hamilton, who missed 3 1/2 years because of his personal problems, played in just 90 games with the Reds last year. He missed time because of gastroenteritis, a sprained right wrist and strained hamstring muscles, but nothing has been bothering him so far this season. He had a sore back coming out of Spring Training, but that has not been an issue during the regular season.

Hamilton said a smarter approach this season has helped his durability. He emphasized stretching and speed during the offseason rather than heavy lifting, and that has helped with the hamstring. He paces himself in his pregame workouts. Last year, he would take 200 swings a day trying to make up for lost time. Now he'll take 25-30 before a game if that's all he needs.

"I'm more prepared for the long haul this year," Hamilton said. "I know what to do and what not to do, what works and what doesn't and I was able to carry it into the season."

He went into Friday's game hitting .322 with six home runs and a league-leading 32 RBIs while playing every game. His "rest" has consisted of three games at designated hitter and six in right field where he doesn't have to run as much into center.

He and David Murphy have become staples in the Rangers outfield. Murphy was supposed to be the Rangers' "fourth outfielder" coming into the season but has started 28 of 30 games. Brandon Boggs, called up from Triple-A Oklahoma on Tuesday, was also in the lineup for the third straight game.

Milton Bradley, who is dealing with sore hamstrings, was at designated hitter Friday. Washington said Bradley might play the field either Saturday night or Sunday afternoon, but the Rangers are being cautious with him. Frank Catalanotto was out of the lineup for the third straight game, all with a right-hander pitching for the other team.

Catalanotto normally plays when there is a right-hander on the mound, but Washington said he has been nursing some nagging injuries. It's also obvious Washington likes what he sees from Boggs, who is a switch-hitter.

"He's certainly talked about as being a part of our future," Washington said. "He's doing well, and I don't want to get him out of there."

Then there is Marlon Byrd, who is on the disabled list with a bone bruise in his left knee. He could be a few days away from going to the Minor Leagues on a medical rehabilitation assignment.

"I'm going to start doing sprints and see how it holds up," Byrd said. "I have good days and bad days, I just don't want to go backward."

Byrd's return will make for a bigger crowd in the outfield. But one thing is obvious: Hamilton is in the lineup every day.