Jon Lester is lined up to start the AL wild-card game should the Oakland Athletics secure one of those two spots.
First, the left-hander has one last chance to help the A's improve their chances of getting there.
Lester attempts to win his fourth straight start Wednesday against a Los Angeles Angels club that's in position to earn home-field advantage throughout the postseason.
Tied with Kansas City for the wild-card lead and three games ahead of Seattle, Oakland (86-71) would confidently rely on Lester (16-10, 2.41 ERA) to start next Tuesday's wild-card game or perhaps even a one-game tiebreaker to determine those participants.
"The fire that he has on the mound ... he pitches with a lot of emotion, and I think guys pick up on that, feed off that," teammate Sean Doolittle told MLB's official website about Lester, who is 6-3 with a 2.20 ERA in 10 starts since coming over from Boston.
He allowed a home run and struck out seven in seven innings of a 3-1 victory over Philadelphia on Friday, lowering his ERA to 1.71 while going 3-2 in his last six starts.
"He still goes out there every fifth day and you know he's going to battle and pitch deep into the game," Doolittle said. "He's been every bit as advertised, probably better, and been that rock for us."
The A's, however, have scored one run with Lester on the mound while he's gone 0-1 with a 2.08 ERA in two starts against the Angels in 2014.
Los Angeles (97-61) remained 2 1/2 games ahead of Baltimore for the best record in the AL with a 2-0 victory Tuesday that evened this three-game set. Wade LeBlanc and four relievers held the A's to seven hits and Gordon Beckham homered for one of the three hits for the West-champion Angels, who are 4-6 since a 10-game winning streak.
Hector Santiago (5-9, 3.98) is 1-0 with a 1.11 ERA in four starts against the A's, but has allowed 10 runs, 12 hits and five walks in only three innings to lose his last two overall. He gave up seven of those runs and never recorded an out in the second inning before leaving a 12-3 loss to Texas on Friday.
"Hector has definitely showed what he can do when he's on," Angels manager Mike Scioscia said. "I think he has to get back and just exhale, had a couple of rough ones, obviously, but his arm is good, his stuff is good, he competes well.
"We'll keep him going and see where everything falls together."
The left-hander followed his latest outing by showering in his full uniform, shaving his head and trimming his beard down to a goatee with hopes of leaving the past behind.
"Clean it out," Santiago said. "Get all the bad effects off ... wash them away."
Josh Reddick, who had three hits Tuesday, is 3 for 7 against Santiago.
Erick Aybar, meanwhile, is 7 for 20 versus Lester and batting .438 in his last nine games against Oakland.