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Ryan Dempster makes his first start as a member of the Texas Rangers this evening when the American League West leaders close out a four-game set with the Los Angeles Angels of Anaheim.

With Colby Lewis lost for the season, Roy Oswalt battling through back issues and Yu Darvish seemingly hitting a wall, the Rangers had been in the market for a starting pitcher. But after the Angels acquired Zack Greinke, Philadelphia signed Cole Hamels to an extension and the asking price being through the moon for both the Phillies' Cliff Lee and Miami's Josh Johnson, Texas seemed to be running out of options.

But, right near Tuesday's non-waiver trade deadline, the Rangers swung a deal with Chicago for Dempster, obtaining the right-hander for a pair of pitching prospects.

"He���s a veteran. He���s been through some wars before," said Rangers general manager Jon Daniels, who team has won two straight AL pennants but no World Series.

Dempster, who will replace Oswalt in the rotation, had power to block deals and refused to approve a trade to Atlanta last week. Reports stated that he only wanted to pitch for the Los Angeles Dodgers, but softened his stance and added the Rangers and New York Yankees to his list of preferred teams.

A 15-year-veteran Dempster was 5-5 with a 2.25 ERA in 16 starts for the Cubs and can become a free agent after the season.

A lifelong National Leaguer, Dempster is 5-6 with a 3.50 ERA in his last 14 starts against AL teams in Interleague Play. Tonight's start, though, will be his first against the Angels.

"He's got savvy and tremendous pitchability," Rangers manager Ron Washington said. "He's a competitor and he has one of the best ERAs in the National League and one of the best opposing batting averages. He's a veteran. He could be exactly what we are looking for in leading our young pitching staff."

After losing the first two games of their set with the Angels, the Rangers managed to pick up a win on Wednesday, as Elvis Andrus capped a four-run 10th inning with a two-run single down the third-base line, carrying Texas to a wild, 11-10, win.

Chris Iannetta hit a solo home run and Albert Pujols hit his second two-run shot of the game in the top of the 10th to give the Angels a 10-7 advantage.

Nelson Cruz led off the home 10th with a bomb to left-center field off Ernesto Frieri, who also surrendered a game-tying home run to Ian Kinsler in the ninth to force extra innings.

Michael Young then reached first on a fielding error by shortstop Andrew Romine and David Murphy followed by working an 11-pitch walk to end Frieri's outing.

Jason Isringhausen (3-1) came on next and gave up a base hit through the left side of the infield from Mike Napoli to load the bases with no outs.

Mitch Moreland's base hit to right plated Young to bring Texas within 10-9 before Andrus pulled the game-winning hit on a 3-2 pitch down the line in left to snap the Rangers' two-game losing streak. Andrus finished the game 4-for-6 with three RBI.

The Rangers, who found themselves down 7-1 after another poor showing from Darvish, now lead the Angels by four games in the AL West.

"That's exactly what we needed. It was just a reminder of what we are capable of right there," said Murphy. "I think anybody in here could say it was one of the most dramatic and best wins they've ever seen."

Joe Nathan (2-3) received the win despite surrendering the home runs to Iannetta and Pujols in the top of the 10th.

Tonight, the Angels will rely on left-hander C.J. Wilson, who is winless in his last six starts (0-3). Wilson's latest setback came on Saturday against Tampa Bay, as he allowed three runs (2 earned) and four hits in 6 2/3 innings to fall to 9-7 to go along with a 2.88 ERA.

It was his first winless calendar month since becoming a full-time starter in 2010.

Wilson, who pitched the first seven years of his career in Arlington, has faced his former team three times this season and is 0-1 with a 4.50 ERA.

Despite Wednesday's loss, the Angels are 7-5 against the Rangers this season.