Concerns about the No. 5 spot in the Texas Rangers’ rotation heading down the stretch are completely valid based on how the starting pitchers who filled that spot fared late last season.

The numbers — 10 starts 10 straight losses — could have cost the Rangers a third straight American League West title though general manager Jon Daniels recently called that an excuse for the Rangers’ September fade.

But when the final margin behind the Oakland A’s was one game one win would have meant a different outcome.

And when Matt Harrison and Colby Lewis were ruled out for the rest of this season and Alexi Ogando hit the disabled list for a third time and a pitcher from Houston’s Triple A team was called upon uncertainty again clouded the fifth spot.

Travis Blackley hasn’t exactly been Sandy Koufax through his two starts but the left-hander hasn’t been the 2012 versions of Scott Feldman Martin Perez and Roy Oswalt either.

Blackley allowed three runs in six innings Monday night and A.J. Pierzynski hit a critical three-run homer in the seventh inning as the Rangers opened a three-game series at Safeco Field with an 8-3 victory over the Seattle Mariners.

The Rangers have won both of Blackley’s starts and his first win with the Rangers helped his new team maintain its 2 ½-game lead over Oakland in the AL West.

“We did have issues last year there and hopefully we don’t have that issue as we move forward with the season” manager Ron Washington said. “He did a great job in his last two outings and we’ll see how it continues.”

Blackley will make another start Sunday against Minnesota Washington said after getting through six innings on only 71 pitches. He changed speeds effectively using his changeup and adding a curveball back to his arsenal.

He allowed five hits including a home run to the Rangers’ newest nemesis Kyle Seager. But he also walked just one batter and worked at a quicker pace than he did in his Rangers debut Aug. 20 against Houston.

“This is a good opportunity” said Blackley who was acquired from the Astros on Aug. 14. “It’s a blessing in disguise. I get a chance to come here looking for October. I’m just trying to run with it.”

Mitch Moreland added a home run in the eighth as the Rangers snapped a two-game losing streak. They scored six times with two outs half of them coming on Pierzynski’s 15th homer of the season.

The blast came on the first pitch from Joe Saunders following an intentional walk to Adrian Beltre and Pierzynski knows that he has to do damage as teams warm to the idea of making someone other than Beltre beat them.