ARLINGTON, Texas -- Scott Feldman said he was simply doing his job, but you wonder if some part of him didn't feel like a lame-duck politician. He's now holding down a spot for Roy Oswalt, who agreed to terms Tuesday in a signing that was announced while Feldman tried his best to get out of the fifth inning of a 10-3 loss to the Seattle Mariners.

Feldman was unsuccessful. And as he walked off the mound, Rangers CEO Nolan Ryan and general manager Jon Daniels were wrapping up the Oswalt announcement in the interview room not far away from the Rangers' clubhouse.

Feldman, who earned a contract extension after winning 17 games in 2009, wants to start. But in four starts this season -- the last two in place of the injured Neftali Feliz -- he hasn't been able to go deep into games or leave with the lead. He's still in the rotation, but only for likely the next three weeks as Oswalt builds up arm strength at Triple-A Round Rock.

"I don't really have a feeling about it," Feldman said. "I just show up here and try to work hard and get ready to do what they ask me to do."

On Tuesday, he didn't get much help from his defense as an errant throw with two outs by Adrian Beltre ended his night before he could finish the fifth.

"It was better than my last one," Feldman said. "Hopefully I can build on it and keep working and next time hopefully I'll get through six or seven innings to help the bullpen."

Feldman said sometimes the miscues happen and he said he hopes to pitch with a little more rhythm his next time out, maybe helping his defenders that way.

"That happens," Feldman said. "You play 162 games. I think maybe if I was pumping more strikes, he would have been on his toes a little bit more."

Feldman hasn't managed to get through five innings in any of his four starts. He says it's not because he's hitting any kind of wall and believes it's coincidental. But he does plan on possibly altering what he's doing between starts to see if that might help.

Daniels made it clear Tuesday that Feldman will continue to pitch until Oswalt is ready. Feldman said that's all he's focused on for now.