SEATTLE -- While the Oakland A's enter their final series of the season in the all-too-familiar position of also-rans, the Seattle Mariners are in somewhat unfamiliar territory.

The Mariners (84-74) will be on their home turf for a late September series that actually matters. Seattle trailed Baltimore by two games in the American League wild-card race and has a legitimate shot at ending its 16-year playoff draught. By taking two of three games against the Houston Astros, the Mariners have kept their postseason chances alive.

"We have a shot," third baseman Kyle Seager told MLB.com after Wednesday afternoon's 12-4 win over the Astros. "We obviously need some help. We can't control that, but we just need to continue to play as long as they'll let us."

The Mariners open the four-game series against the hapless A's (67-91) on Thursday needing to win at least three games to have a realistic chance of staying in contention. Adding to the complication is a Detroit team that sits between Seattle and Baltimore's current spot for the second wild-card berth, meaning the Mariners are going to need two teams to stumble at the finish line if they're going to have any kind of a shot at getting into the postseason.

Seattle has not been to the postseason since winning 116 games in 2001. The Mariners own the longest playoff draught in Major League Baseball and are the only American League to never make an appearance in the World Series. Star pitcher Felix Hernandez, who is scheduled to start Sunday's regular-season finale, has never pitched in a postseason game.

Hernandez and fellow veteran Hisashi Iwakuma are scheduled to pitch the two weekend games, but the Mariners will rely on a pair of youngsters to keep them in the race until then. Ariel Miranda, a 27-year-old rookie, is scheduled to start Thursday's series opener, while 24-year-old Taijuan Walker is on tap to start Friday.

Miranda (5-2) has been a surprising contributor to a team that acquired him at the trade deadline. At the time, Seattle was falling out of playoff contention and traded veteran starter Wade Miley to Baltimore in an effort to get younger. Miranda, coincidentally, has since joined the rotation and now might be a key to Seattle catching the Orioles in the wild-card race.

Oakland will go with 25-year-old Kendall Graveman, who is about as close as the young A's have to a veteran starter. Graveman (10-11) got tagged for 12 hits and eight runs in a 14-3 loss to Seattle 2 1/2 weeks ago, and he's failed to beat the Mariners in four tries this season -- going 0-3 with a no-decision. He can't expect much offense from a team that has scored an AL-low 638 runs heading into the Seattle series.

The A's are 26 1/2 games behind division-leading Texas and were officially eliminated from the wild-card hunt earlier this month, so the only motivation is playing the role of spoiler to a longtime West Coast rival.

"They're right in the middle of it and I think that will be good for our guys, too," Oakland manager Bob Melvin told The San Francisco Chronicle this week. "Nothing is on the line for us, but whenever you're in that atmosphere, there's an intensity to it that's similar to postseason.

"It'll be good for us, inspirational. There will be big crowds and lots of excitement. Good for them, and hopefully good for us, too."