ARLINGTON -- Rangers starters averaged 6 1/3 innings per start over their first 10 games, but are down to 4 1/3 innings per start in their last seven.

The starters also went at least six innings in eight of their first 10 starts, but C.J. Wilson is the only starter to go six innings over the last seven. On Saturday night, Scott Feldman lasted just 3 2/3 innings, and the Rangers needed 4 1/3 scoreless innings from Doug Mathis to get through the game without wrecking the bullpen.

The 'pen, going into Sunday, is third in the American League in innings pitched, and Mathis is tied with four other pitchers for most relief innings in the league with 12. Dustin Nippert and Mathis are two of 13 AL relievers who have pitched at least 10 innings.

"It's putting a heavy load on the bullpen, but some guys have been stepping up," manager Ron Washington said. "Mathis stepped up and saved us. We certainly want to see these guys get deeper. Having to pick up four or five innings every night, sooner or later, is going to hurt you. Those guys have to go deeper in the game, no doubt about it."

Rangers being cautious with Saltalamacchia

ARLINGTON -- Catcher Jarrod Saltalamacchia is still experiencing some tightness in his back and left shoulder, and the Rangers are not ready to recall him from his medical rehabilitation assignment.

"Structurally, he's fine and has been cleared by the doctors to play," general manager Jon Daniels said Sunday. "He's dealing with some tightness in his shoulder that he's able to work through with his pregame routine and stretching. But he still feels some effects on the field during the game.

"He has expressed that he wants to play through it and the doctors say he won't hurt it. But until he's 100 percent ... he's not ready to come back."

Matt Treanor was back at catcher for the fifth time in seven games. He has also started seven of the last 11.

Saltalamacchia will get Sunday off and play again for Oklahoma City on Monday. He has played five games at Oklahoma City on rehab assignment, including four at catcher. A rehab assignment for position players lasts 20 days. At that point, if he's still not ready, the Rangers will have to activate Saltalamacchia or option him to the Minors.

"We're playing it day by day," Daniels said. "At some point, we'll make a call."

Saltalamacchia has been dealing with issues in his neck and both shoulders since being diagnosed with thoracic outlet syndrome last August. He had surgery in September to have a rib bone removed that was causing pain and numbness in his right arm. He has since had several setbacks in his recovery and went on the disabled list after just two games this season.

The biggest concern is his throwing, both back to the pitcher and to bases. The tightness that he is currently experiencing continues to have an impact.

"His throwing has been OK, not great," Daniels said. "He feels it with some swings and some throws. Our scouts say he's been aggressive with his throwing. But until he's 100 percent, he's got to continue to work through it.

"We'd like to have him back, but we're not bringing him back until he's ready."

Hamilton gets first day off

ARLINGTON -- Josh Hamilton was given his first day off on Sunday with David Murphy starting in left field. Hamilton had a three-hit game on Wednesday in Boston, but is 2-for-13 since, including 1-for-5 on Saturday. "He just looked a little sluggish last night," manager Ron Washington said. "This gives me another chance to get Murphy in there and give Hamilton a chance to re-energize himself."

Murphy went into Sunday's game with three hits in 22 at-bats, including going 0-for-4 with four strikeouts on Friday. Shortstop Elvis Andrus and third baseman Michael Young are the only two players who have started every game.

Worth noting

Second baseman Ian Kinsler (sprained right ankle) is expected to start a rehab assignment with Double-A Frisco on Monday. ... The Rangers, going into Sunday's game, had held a four-run lead in their last three losses. ... Justin Smoak had walks in his first two games with the Rangers. The last player to do that was Ruben Mateo on June 12-13, 1999.