After thousands of games and months of toil to get to this point, it's amazing how much can happen in a matter of moments during the final days of baseball's September stretch run.
In one city, the oldest position player in the game sends a playoff-hungry home crowd into a frenzy with a walk-off homer. In another, a rookie pitching his team toward a division title comes within an eyelash of throwing himself right into the history books with a no-hitter. In yet another, a loss in extra innings spells the end of the road for one of last year's postseason darlings.
All in the span of about 10 minutes.
As the Pulse of the Postseason pounded loudly across the country on the final Tuesday night of the regular season, Jason Giambi's 42-year-old swing kept the Indians in control of an American League Wild Card spot, young Michael Wacha of the Cardinals danced with immortality and the Orioles dropped out of the hunt for that position.
On a night when the defending American League champion Tigers clinched a postseason spot but remain one win away from a division title, their upstart division rivals in Cleveland wound up making the most noise, in more ways than one.
"It's stuff you dream about," Giambi said after his walk-off shot.
The Indians were on a roll coming into Tuesday's game and had the White Sox down to their last three outs. But closer Chris Perez gave up two solo home runs to allow the White Sox to take the lead, and in exchange heard from the fans as he was walking off the mound.
Ah, but three outs remained for the Indians, too. And one veteran named Jason Giambi, available for duty.
"He's always ready," Indians manager Terry Francona said. "And that's why he's playing this game, because he wants to win, and he's willing to do anything for anybody at any time. Fortunately for us, sometimes it's when he steps in the batter's box."
With two outs and Michael Brantley standing on second, Giambi turned on a 1-and-1 slider from Addison Reed, crushing the ball deep into the right-field stands for a 5-4 victory -- and the requisite scrum at home plate, the oldest guy on the team right in the middle of it all.
It was Cleveland's 11th walk-off win of the season and Giambi's second pinch-hit homer to win a game, making him the oldest player ever to hit a walk-off shot, again. More than any of that, it was a win that looked like a loss and became the biggest win of the season for a team itching for a chance at the postseason.
"It's the top of the world right now," Giambi said of his homer after the Indians' fifth straight win. "I don't even think I touched the ground."
But even while Cleveland fans were sent leaping out of their seats to the tune of the crack of a bat, fans in St. Louis were on their feet, cheering on yet another Cardinals pitching phenom as he pushed his way to his 26th out without allowing a hit. One more, and he would be the 22nd rookie ever to complete a no-hitter.
And how close could it have been? As close as a Ryan Zimmerman chopper nearly tipping off Wacha's outstretched glove, as close as Pete Kozma's barehanded grab and quick throw could be to allowing Matt Adams to tag Zimmerman before he reached first base.
It was the third time this season a no-hitter had been broken up with two outs in the ninth -- Yu Darvish of the Rangers and Yusmeiro Petit of the Giants both coming so very close, too. Wacha left to a standing ovation before Trevor Rosenthal finished up a 2-0 win.
And in Baltimore, the Orioles worked overtime -- playing in the Majors' 238th extra-inning game, beating the previous all-time high set in 2011. But they didn't go deep into the night, as RBI singles by Toronto's Mark DeRosa to tie it in the eighth and go ahead in the 10th led to a 3-2 defeat of the Orioles.
"We play all the way from February 15th or whenever we started to get to the playoffs," said O's shortstop J.J. Hardy. "It's hard to think that after how many games we've played since then, we're not going. So yeah, it's tough."
The simultaneous scoreboard of September's stretch run continued into the night, with the NL Central race and the AL Wild Card still sharing center stage.
With the Cardinals winning at home behind Wacha's gem, the Pirates got ahead of the Cubs early and held on for an 8-2 victory, while the Reds absorbed a 4-2 loss to the Mets at home. That means the division race goes Cardinals on top with a magic number of three, the Pirates two behind them and the Reds another game back as the two Wild Card entrants.
The Cardinals remain a half-game behind the Braves -- 3-2 walk-off winners over the Brewers -- in the race for the top seed in the National League. The Dodgers, winners of the NL West and two games behind Atlanta -- edged Giants late Tuesday, 2-1.
In the AL Wild Card quest, while the Indians were showing the kind of resilience teams need to get through the last week and move on to another, the Rays were adding on at Yankee Stadium toward their fifth straight win. The Rays got a leadoff homer from Matt Joyce in a three-run top of the first and never looked back, taking a 7-0 victory that keeps them in the top Wild Card spot and puts the Yankees on the brink of elimination.
The Rangers remained right in the tight race for the Wild Card with a 3-2 win over the Astros, keeping them one game behind the Indians, but the Royals sustained a tough loss -- they all are now -- in a 4-0 blanking in Seattle, dropping Kansas City's elimination number to two with the Indians.
In the race for the best record in the American League, the Red Sox entered the day one game ahead of the A's, and Boston dropped its Interleague game at Colorado, 8-3. Oakland followed suit with a 3-0 loss at the Angels, keeping that race the same.
But nowhere could there be quite the celebration, quite the turn of events as what the Indians and the fans at Progressive Field experienced after Giambi's bat met ball and ball met bleachers -- later delivered to the Indians' clubhouse for posterity.
In the final Tuesday in September, memento-worthy moments are just beginning.
Another day, another clinch on the horizon as the days and games tick down toward the final weekend of the season, the tension thick and the remaining time increasingly thin.
With the Pulse of the Postseason picking up early with afternoon games Wednesday and contests into the night holding October implications, the Tigers are the team holding a celebration in their own hands.
A win at Minnesota on Wednesday night would clinch a third consecutive American League Central crown for the defending league champs. So, too, would an Indians loss at home against the White Sox, but the Tigers to be certain would like to handle their own business.
"We're not celebrating because we haven't done what we want to do," said Tigers manager Jim Leyland, who clinched a fourth postseason berth in his eight years in Detroit.
Waiting around for the Indians to lose won't work. The Tribe pulled out a fifth straight victory in walk-off fashion Tuesday and has won 10 of the last 12 heading into Wednesday night's game.
The AL Wild Card-leading Rays are at Yankee Stadium for the finale of a three-game set, holding that slim one-game lead over the Indians, who own the coveted No. 2 Wild Card spot. The Rangers take on the Astros again one game out of the mix, and the Royals could see their turnaround season end just short of its goal if they lose and the Indians win. The Royals will be meeting a Cy Young candidate in Seattle's Hishashi Iwakuma, proving there's a luck of the draw to this stretch run, too.
The NL Central tussle will continue with a trio of games in the afternoon, the division-leading Cardinals hosting the Nationals with starter Jordan Zimmermann going for his 20th win, the second-place Pirates wrapping up a set at the Cubs, and the Reds will play at home looking to avenge Tuesday's loss to the Mets, one game behind the Pirates with the Bucs heading to town on the weekend.
The competitions for each league's top record, and therefore home-field advantage through the playoffs, are tight heading into Wednesday's games as well.
In the NL, the Braves will host the Brewers with a half-game lead and the tiebreaker over the Cardinals. The Dodgers, who incidentally have moved to within two games of Atlanta, will close out a series at San Francisco.
In the AL, both are on the road as the Red Sox meet the Rockies and the A's meet the Angels, Boston holding a one-game lead over Oakland -- and, after they split the season series, the second tiebreaker of intradivision games by a half-game.
Wednesday's key games to watch (all times ET)
Mets (Matsuzaka, 2-3) at Reds (Latos, 14-6), 12:35 p.m. Preview >
Nationals (Zimmermann, 19-8) at Cardinals (Miller, 14-9), 1:45 p.m. Preview >
Pirates (Liriano, 16-7) at Cubs (Arrieta, 4-4), 2:20 p.m. Preview >
Athletics (Straily, 10-7) at Angels (Weaver, 10-8), 3:35 p.m. Preview >
White Sox (Axelrod, 4-10) at Indians (Salazar, 1-3), 7:05 p.m. Preview >
Rays (Price, 8-8) at Yankees (Hughes, 4-13), 7:05 p.m. Preview >
Brewers (Lohse, 10-10) at Braves (Maholm, 10-10), 7:10 p.m. Preview >
Astros (Keuchel, 6-9) at Rangers (Perez, 9-5), 8:05 p.m. Preview >
Red Sox (Peavy, 11-5) at Rockies (Chacin, 14-9), 8:40 p.m. Preview >
Royals (Santana, 9-9) at Mariners (Iwakuma, 13-6), 10:10 p.m. Preview >
Dodgers (Nolasco, 13-10) at Giants (Zito, 4-11), 10:15 p.m. Preview >
If the postseason started today ...
Wild Card: Indians at Rays
Division Series: Wild Card at Red Sox^ | Tigers* at A's^
Wild Card: Reds* at Pirates*
Division Series: Wild Card at Braves^ | Dodgers^ at Cardinals*
* - clinched postseason spot
^ - clinched division
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 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 the division record is tied, then intraleague 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. If the division record is tied, then intraleague record will be the next tiebreaker.
• Tiebreaker rules »
2013 postseason schedule
NL Wild Card Game: Oct. 1
AL Wild Card Game: Oct. 2
NL Division Series begin: Oct. 3
AL Division Series begin: Oct. 4
NL Championship Series begins: Oct. 11
AL Championship Series begins: Oct. 12
World Series begins: Oct. 23
John Schlegel is a national reporter for MLB.com.