Count Saturday as a day of missed opportunities across Major League Baseball, as a handful of teams couldn't capitalize on the chance to enhance their postseason position.
In the American League, the top three Wild Card contenders all lost, meaning they are still separated by a razor-thin one-game margin.
And in the National League, the Dodgers squandered a golden opportunity in the afternoon, blowing a five-run seventh-inning lead. But their NL West rivals, the Giants, couldn't take advantage, as the Padres' pitching staff shut down the San Francisco offense for a second straight night.
IF THE POSTSEASON STARTED TODAY ...
Wild Card:Royals at A's
Division Series: Wild Card at Angels | Tigers at Orioles
Wild Card: Pirates at Giants
Division Series: Wild Card at Nationals | Cardinals at Dodgers
• Postseason picture
Saturday's action got off to a thrilling -- yet controversial -- start, with the Tigers holding off a furious challenge in Kansas City for a 3-2 win.
With the Tigers and Royals tied at one in the sixth inning, Kansas City's Omar Infante hit a line drive at Ian Kinsler, who threw the ball away at second base, and it looked like the Royals had taken a 2-1 lead.
But Royals catcher Salvador Perez had never fully returned to the third-base bag to tag up, and he was eventually ruled out. Tagging up on a fly ball (or a line drive, in this case) is not reviewable, and when the umpires called into the Replay Operations Center New York, they were told the play couldn't be looked at. But their conference in the infield led them to the correct conclusion anyway.
Meanwhile, in Saturday's other early afternoon game, the Dodgers held a comfortable 7-2 lead at stretch time in Wrigley, only to see that slip away.
Cubs left field Chris Coghlan went 4-for-4 with a pair of homers, and the North Siders rallied, playing spoiler with an 8-7 victory.
As the day progressed into the late afternoon, the AL Wild Card took center stage, beginning with Oakland's 3-0 loss to Philadelphia. The A's mustered just four hits against Jerome Williams and a pair of Phillies relievers.
But the Mariners couldn't capitalize on the losses by Kansas City and Oakland, as they fell behind by four runs in the first inning against Houston and eventually lost, 10-1. The three clubs, who are fighting for two spots, remain separated by just one game. The Indians, meanwhile, sit 3 1/2 games back after their victory over Minnesota.
In the NL Wild Card hunt, Milwaukee cut its deficit on the Pirates to 3 1/2 games with a 1-0 win thanks to Logan Schafer's ninth-inning sac fly in Pittsburgh. A win on Sunday would not only give the Brewers a series victory, but it would put them right back in the playoff hunt after many had left them for dead Friday night.
The Cardinals capitalized on Pittsburgh's loss, beating the Reds, 8-4, to drop their magic number to clinch the NL Central to five. But the Giants couldn't take advantage, as the offense struggled in San Diego for a second consecutive night.
San Francisco leads Pittsburgh by one in the race for home-field advantage in the Wild Card Game. But perhaps more important, the Giants didn't make up any ground on the Dodgers, whose magic number in the NL West also sits at five entering play Sunday.
TODAY'S KEY GAMES TO WATCH (all times ET)
Brewers (Peralta 16-10, 3.70) at Pirates (Worley 7-4, 3.18) 1:35 p.m. Preview
The Brewers have a chance to jump right back into the Wild Card conversation, but they'll need Wily Peralta to continue his recent hot streak. He has a 2.75 ERA in three September starts.
Tigers (Porcello 15-11, 3.19) at Royals (Guthrie 11-11, 4.35) 2:10 p.m. Preview
Detroit has a chance to take firm control in the AL Central with Rick Porcello on the hill, and the right-hander has a 2.18 ERA in three starts against Kansas City this season.
Mariners (Iwakuma 14-8, 3.42) at Astros (McHugh 10-9, 2.66) 2:10 p.m. Preview
The Mariners remain a game back in the loss column of both Oakland and Kansas City, and on Sunday they face Astros righty Collin McHugh, one of the league's hottest pitchers. McHugh is 6-0 with a 1.54 ERA in his last seven starts.
Dodgers (Wright 5-4, 4.30) at Cubs (Turner 5-10, 6.20) 2:20 p.m. Preview
With either a win on Sunday or a Giants loss, the Dodgers would set themselves up to clinch against their Bay Area rivals this week, by winning two of three at Dodger Stadium.
Phillies (Burnett 8-17, 4.40) at A's (Kazmir 14-9, 3.44) 4:05 p.m. Preview
The A's are clinging to the top Wild Card spot (and home-field advantage in the always-nervy Wild Card Game), but they'll need an improved performance from struggling lefty Scott Kazmir, who is 3-6 with a 6.29 ERA since the beginning of August.
Giants (Vogelsong 8-11, 3.98) at Padres (Kennedy 11-13, 3.80) 4:10 p.m. Preview
Offense hasn't come easy for the Giants this weekend at Petco Park, and they'll look to change that on Sunday. Ryan Vogelsong, who has struggled all season on the road, gets the start.
Reds (Simon 14-10, 3.35) at Cardinals (Lynn 15-9, 2.68) 8 p.m. Preview
A victory Sunday night behind a red-hot Lance Lynn would ensure a postseason berth and inch the Cardinals closer to a second consecutive NL Central crown. Right now, with their rotation lined up nicely for the final week, it's their division to lose.
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.
AL East: Orioles clinched
AL Central: Tigers seven over Royals
AL West: Angels clinched
AL Wild Card 1: A's nine over Royals
AL Wild Card 2: Royals nine over Mariners
NL East: Nationals clinched
NL Central: Cardinals five over Pirates
NL West: Dodgers five over Giants
NL Wild Card 1: Giants eight over Pirates
NL Wild Card 2: Pirates five over Brewers
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 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
AJ Cassavell is a reporter for MLB.com. Follow him on Twitter @ajcassavell.