With a 6-2 loss to the Tigers on Wednesday, the A's have dropped three straight, their hold on the top American League Wild Card spot no longer so secure. By the time Oakland finished its game in Detroit, it was tied with Baltimore for that first spot, but an Orioles win over Seattle put the A's a half-game back.

Over in the AL West, the A's sit four games behind the division-leading Rangers, who upped their advantage with a win over the Angels on Wednesday.

The going only gets tougher for the A's, whose series finale in Detroit on Thursday is to be followed be a three-game set in New York and four ensuing games in Texas.

"Certainly we need to win some games," Seth Smith said, "and that starts tomorrow with one win."

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

A's (Milone, 13-10) at Tigers (Sanchez, 8-12), 1:05 p.m. Preview >

Blue Jays (Laffey, 3-5) at Yankees (Hughes, 15-12), 7:05 p.m. Preview >

Red Sox (Buchholz, 11-6) at Rays (Price, 18-5), 7:10 p.m. Preview >

White Sox (Liriano, 6-11) at Royals (Guthrie, 4-3), 8:10 p.m. Preview >

Rangers (Darvish, 15-9) at Angels (Greinke, 14-5), 10:05 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