In what have been dismal ends to rough seasons for the Seattle Mariners and Oakland Athletics, some relief will come for one of them in the final series.

The Mariners try to snap out of their funk by continuing their 2015 dominance over the A's at Safeco Field on Friday night.

Seattle (75-84) has lost seven of eight but is 12-4 against last-place Oakland (66-93), including wins in five of six at Safeco. Another victory would give the Mariners more against the A's than any other team while upping Oakland's highest loss total against an opponent.

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Felix Hernandez is 3-1 with a 3.09 ERA against the A's this year, but Oakland catches a break as Mariners manager Lloyd McClendon announced Wednesday the ace would not pitch in the final series - ending his bid for seven straight seasons with 200 strikeouts and 200 innings.

"I was holding out some hope that we would get back in this thing but I'm just not going to stress him anymore this year," McClendon told MLB's official website. "The future of this organization is much bigger than one or two games."

Hisashi Iwakuma suffered Seattle's lone loss to Oakland at home, but earlier this month helped the Mariners to their second five-game winning streak against the A's this season. The right-hander will try to extend that to six, which would be the Mariners' longest in the series since 2009.

Iwakuma (9-5, 3.67 ERA) finished off a sweep in Oakland on Sept. 6 by holding the A's to one run in 6 1-3 innings of a 3-2 victory. Two weeks earlier, though, he was rocked by Oakland for seven runs in 4 2-3 innings of an 11-5 loss.

Billy Butler homered off Iwakuma in the second matchup while Danny Valencia hit a two-run shot off him in the earlier game, capping a seven-run fifth inning that flipped Iwakuma's 5-0 lead into a 7-5 deficit.

Josh Reddick is 6 for 18 with a triple against Iwakuma in his career. Butler is 4 for 13 with five strikeouts, Eric Sogard 5 for 17 with two doubles and Coco Crisp 4 for 19 with a double and two home runs in the matchup.

Iwakuma went 3-2 with a 2.18 ERA in five September starts, striking out 29 and walking three. He gets his final chance to hit double-digit wins for the third straight season.

Oakland has lost nine of 11 and has the highest ERA in baseball since Sept. 19 at 7.58. The starters have posted an 8.08 ERA in that span, a number Aaron Brooks will look to lower in his ninth start.

Brooks (2-4, 7.26), though, has a 10.00 ERA in his last six outings, including a six-run, 2 1-3-inning effort in an 11-8 loss to Seattle on Sept. 4. The right-hander is 1-2 with an 8.27 ERA in four road starts this year.

He'll try to shut down a Mariners team that ranks near the bottom of the major leagues with 3.9 runs per game at home. Seattle, however, has scored 5.7 there against the A's.