ST. PETERSBURG -- The Rays claimed a dramatic 7-4 walk-off win over the Red Sox on Thursday night to at least make them believe they still have a chance to sneak into the postseason.

Meanwhile, the American League East-leading Yankees won their fifth consecutive game to maintain a 6 1/2-game lead over the Rays. In the AL Wild Card race, the Orioles and A's boast identical 85-64 records, so Tampa Bay sits 5 1/2 games back.

The Rays have 12 games remaining and find themselves seven games from being mathematically eliminated from the AL East race and eight games from being eliminated from the AL Wild Card race.

"We have to continue to pitch well, play our defense," manager Joe Maddon said, "but if the hitting happens to come through at this time, there's no telling what we can do."

Friday's key games to watch (all times ET)

Twins (Deduno, 6-4) at Tigers (Porcello, 9-12), 7:05 p.m. Preview >

A's (Parker, 11-8) at Yankees (Sabathia, 13-6), 7:05 p.m. Preview >

Orioles (Gonzalez, 6-4) at Red Sox (Lester, 9-12), 7:10 p.m. Preview >

White Sox (Peavy, 11-11) at Angels (Santana, 8-12), 10:05 p.m. Preview >

Rangers (Perez, 1-1) at Mariners (Iwakuma, 6-5), 10:10 p.m. Preview >

If the postseason started today ...

This is how the teams would match up:  Postseason Bracket »

Postseason 101

Magic numbers
To calculate a team's magic number, take the number of games it has remaining and add one. Then subtract the difference in the number of losses between that team and its closest pursuer.

Tiebreaker scenarios
A tiebreaker game will be played to determine a division winner, even if the tied clubs are assured of participating in the postseason. If a division championship tiebreaker is necessary, the head-to-head record between the clubs will determine home-field advantage. If the head-to-head record is tied, then the division record will be the next tiebreaker.

If two clubs are tied for the two Wild Card berths, home-field advantage will be determined by the head-to-head record between the clubs. If the head-to-head record is tied, then the division record will be the next tiebreaker.

Tiebreaker rules »

2012 postseason schedule
Wild Card playoff games: Oct. 5
Division Series: Oct. 6-12
AL Championship Series: Oct. 13-21
NL Championship Series: Oct. 14-22
World Series: Oct. 24-Nov. 1