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Hisashi Iwakuma takes another crack at win No. 13 on Sunday when the Seattle Mariners conclude a four-game series with the Houston Astros at Minute Maid Park.

Iwakuma has been terrific for the Mariners this season, posting a 12-6 mark to go along with a 3.03 ERA. The Japanese right-hander, though, did not get a decision on Tuesday against Texas, as he allowed three runs and seven hits and struck out seven in six innings of a 4-3 loss.

"I thought they did a nice job, made him work," Seattle manager Eric Wedge said. "They were fouling some pitches off, he threw some pitches but he controlled damage though. What was even more impressive than that was the way he came back after that and got us deeper in the ballgame. Gave us six innings with those three runs."

Iwakuma is 2-1 in three starts against the Astros with a 1.89 ERA.

Houston, meanwhile, will hand the ball to right-handed rookie Brett Oberholtzer, who is 3-1 with a 3.43 ERA. Oberholtzer did not get a decision on Monday in Chicago, as the White Sox reached him for five runs (4 earned) and eight hits in 5 1/3 innings of his team's 10-8 win.

"I battled myself more so tonight than I ever have being up here in the big leagues. You know what, that's going to happen," Oberholtzer said. "I'm not going to have great outings all the time, great results. Tonight was a testament of myself battling and trying to make quality pitches, even though I didn't feel that great tonight."

Seattle's recent road prowess continued on Saturday, as Joe Saunders and three Mariners relievers continued to keep the light-hitting Astros off balance in a 3-1 victory.

Saunders (11-13) allowed just one unearned run on six hits over 5 1/3 innings, while Carter Capps, Yoervis Medina and Danny Farquhar kept the Astros off the board the rest of the way.

"We had opportunities offensively and misplayed some balls defensively, (but) in the end we won the ball game," said M's manager Eric Wedge.

Seattle has now won five in a row away from home, its best stretch since winning six in a row on the road from April 17-30, 2011.

Houston starter Dallas Keuchel (5-8) faced the minimum from the second through the seventh innings, but the only run of support he got came in the fourth when Brandon Barnes scored on a Nick Franklin error.

In fact, the Astros finished 0-for-8 with runners in scoring position and have managed a mere eight runs during their five-game slide.

"We just can't seem to be able to get the big hit," Astros manager Bo Porter said.

Seattle has won 10 of 15 from the Astros this season and has won eight of the last nine matchups.