A's hand Straily ball in Seattle

Dan Straily attempts to win his fourth straight decision on Saturday as the Oakland Athletics take on the Seattle Mariners in the second game of a weekend set at Safeco Field.

Straily was roughed up in his latest start, yielding eight hits and six earned runs in less than five innings of work against the Rangers, but he escaped with a no-decision.

"I was up in the strike zone. They were aggressive and I just got beat, plain and simple," Straily said of his last outing. "They got me, that's all there is to it."

On the season, Straily is 4-2 with a 4.97 ERA, and he has not lost since May 15. One of his two defeats came against the Mariners on May 10, when he allowed six earned runs in five innings, scattering six hits and walking a season-high four batters.

For Seattle, Aaron Harang will toe the rubber attempting to improve upon his 3-7 record and 5.28 ERA.

Harang was masterful in a June 11 win over Houston, pitching a two-hit shutout while striking out 10 and walking none, but he followed that up with a clunker, yielding 11 hits and four runs, one earned, in a June 17 loss to the Angels.

The 12-year veteran, who debuted with the Athletics in 2002, has faced his former team just once before, putting together an ugly outing last season as a member of the Dodgers (3.2 IP, 3 H, 3 ER, 8 BB).

The Athletics continued their reign atop the AL West standings on Friday night by claiming the series-opener against the Mariners, 6-3.

Yoenis Cespedes shined in the victory by belting his 14th and 15th home runs of the season, finishing with a season-high four RBI. Cespedes hit one of his longballs in the first inning to give the A's the lead and his other in the ninth to give his team some breathing room.

Coco Crisp and Jed Lowrie also went deep for the away team.

Bartolo Colon continued to defy Father Time in the win, allowing three earned runs in eight innings of work. The 40-year-old right-hander has won seven straight starts and sits with a 2.93 ERA.

Grant Balfour struck out two batters in a scoreless ninth inning for his 18th save.

Hisashi Iwakuma had a rare poor outing for the Mariners, yielding four earned runs over seven innings of work, although he allowed only six total baserunners and struck out six.

Nick Franklin gave Seattle a shortlived lead in the bottom of the third inning after blasting a three-run home run, his fourth of the season. Justin Smoak finished with two hits.

Oakland has claimed back-to-back wins over Seattle after the Mariners had won the previous three contests.