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The Texas Rangers signed Roy Oswalt earlier this season to bolster their rotation, but his struggles and some other additions have relegated the veteran to the bullpen.

Oswalt, though, makes his second straight spot start on Thursday evening in the opener of a four-game series with the Minnesota Twins.

After spending last season with the Philadelphia Phillies, Oswalt didn't sign with the Rangers until late May and spent time in the minors getting game ready before making his first start with the big-league club on June 22.

He won that outing with 6 2/3 innings of one-run ball, but was 4-2 with a 5.53 earned run average through seven starts before getting sent to the bullpen following the acquisition of Ryan Dempster prior the non-waiver trade deadline.

The right-handed Oswalt made three relief outings before filling in for Dempster, who was away from the team for personal reasons, on Saturday against the Toronto Blue Jays. Oswalt allowed a run on two hits and a pair of walks in 4 2/3 innings of work, getting a no-decision in his first start since July 30 and first appearance since Aug. 8.

"It went better than I thought it would. First couple of innings I felt really good and the ball kind of came up a little bit later," said Oswalt, who threw just 62 pitches.

The 34-year-old gets the call again for this opener with Yu Darvish scratched because of a tight right quad. Oswalt, who is 1-1 in four lifetime outings versus the Twins with a 4.23 ERA, doesn't see himself as a fixture in the rotation however.

"I don't think I'm in the rotation. I think I'm just making another start," Oswalt said on Texas' website. "I'm just doing what I'm told. If they tell me I need to start Thursday, that's what I'll do. They haven't explained what kind of role I'm in."

Oswalt could be in line for any easy day if the Rangers' offense produces like it did on Wednesday in a 12-3 win over the Baltimore Orioles.

Adrian Beltre hit three home runs, including two in a nine-run fourth inning, and Mitch Moreland added a grand slam as the duo drove in 10 of Texas' runs.

"Finally, I got a good game offensively. I've been struggling a couple of weeks, driving the ball. I hit the ball hard in the air," said Beltre, who became the 57th player in major league history and second this season to homer twice in one inning.

Derek Holland allowed three runs on five hits and struck out five over seven innings to snap a four-start winless stretch.

Texas won for the fifth time in seven games and is five games up on the Oakland Athletics for first place in the AL West.

Scott Diamond will try contain the Rangers this evening and has logged back- to-back no-decisions for the Twins while giving up five runs over 13 2/3 innings in that time.

The 26-year-old southpaw yielded two runs on nine hits over 6 2/3 frames at the Seattle Mariners on Saturday, leaving him 10-5 with a 2.95 ERA in 19 starts this year.

Diamond faces the Rangers for the first time and hopes the Twins can avoid a 12th loss in 14 games following Wednesday's 5-1 setback to the A's.

Liam Hendriks remained winless after 13 major league starts. Oakland tagged the right-handed Aussie for four runs on six hits and three walks in five innings.

"He's gotta be a little bit better than that with the strike zone and work ahead a little better," Twins manager Ron Gardenhire said. "He's behind a lot of hitters. But, like I said, he competed in some big situations and got out of some jams he created for himself. There's a step in the right direction."

The Rangers have won five of six against the Twins this season, including two of three in Texas.