Meanwhile, back East, as in American League East, the Yankees beat Baltimore, 13-3 on Sunday and reclaimed their one-game division lead. In the AL Central, the Tigers and White Sox both lost, meaning Chicago kept its two-game advantage on Detroit, setting up what could be a memorable four-game set between the two clubs, also beginning Monday, at U.S. Cellular Field.
"We've got to move on," Tigers center fielder Austin Jackson said Sunday after his team was swept by the Angels. "We're definitely a little frustrated, but at the same time we are looking forward to playing better baseball over in Chicago."
The NL East and Central both continue to belong to the Nationals and Reds, respectively, while the Giants exited their Sunday-night showdown with their rival, the second-place Dodgers, with a healthy 5 1/2-game lead over Los Angeles in the NL West.
Other events of note as the pennant races heat up with each day at the ballparks of America: a Tampa Bay Rays victory over Texas on Sunday that put Joe Maddon's gang within two games in the AL East (and one in the Wild Card race), and the Braves' fifth win in a row, which got them within 5 1/2 games of Washington and solidified their Wild Card lead.
The Cardinals beat the Brewers in extra innings on Sunday and are in the other Wild Card slot for the NL heading into Monday.
Today's key games to watch (all times ET)
Pirates (Rodriguez, 10-13) at Reds (Latos, 12-4), 7:10 p.m. Preview>
The Reds are comfortably ahead in the NL Central, but the Pirates can make a big statement in this series, particularly for their Wild Card hopes, being that they're entering this set 2 1/2 games back.
Nationals (Gonzalez, 18-7) at Mets (McHugh, 0-1), 7:10 p.m. Preview>
The first week of Life Without Stephen Strasburg begins. Good thing the Nationals have a legitimate Cy Young Award candidate in Gio Gonzalez, who starts here, and a healthy NL East lead.
Braves (Minor, 8-10) at Brewers (Peralta, 1-0), 8:10 p.m. Preview>
Atlanta's getting hot again at the right time. Sunday's win was the Braves' fifth in a row. They'll be looking to add a bit of offense to their sterling recent starting pitching.
Tigers (Porcello, 9-11) at White Sox (Quintana, 5-4), 8:10 p.m. Preview>
All eyes should be on this series, with Detroit two games back of the South Siders heading into this huge four-gamer.
Giants (Vogelsong, 12-7) at Rockies (White, 2-8), 8:40 p.m. Preview>
The Giants have a nice little cushion in the NL West. They'll need to take advantage of it here and get the best of the Rockies while the Dodgers are without injured slugger Matt Kemp.
A's (Parker, 9-8) at Angels (Haren, 10-10), 10:05 p.m. Preview>
Another huge series. The Angels are hotter than anyone, with six consecutive victories, and they're coming after the banged-up A's in the division and Wild Card standings. Four games in Anaheim is exactly what Scioscia wants right now. We'll see if his club makes the most of it. Meanwhile, the A's have won nine in a row on the road.
Cardinals (Garcia, 5-6) at Padres (Stults, 4-2), 10:05 p.m. Preview>
The Cardinals are where they need to be right now -- in front for one of the Wild Card spots. The Padres have been better of late, which makes this West Coast jaunt a tough assignment for Mike Matheny's Redbirds.
If the postseason started today ...
Wild Card: Orioles at A's
Division Series: Yankees vs. White Sox | Rangers vs. Wild Card winner
Wild Card: Cardinals at Braves
Division Series: Reds vs. Giants | Nationals vs. Wild Card winner
Postseason Bracket »
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.
A tiebreaker games 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 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 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