The beginning of September offers baseball fans a prime opportunity to take a step back and evaluate the ongoing pennant races, and boy are there some appetizing ones this year.
Of course, as we've come to learn over the past few seasons, Sept. 1 is only a benchmark. It's by no means a tell-all indicator of future results.
In fact, one glance at the end-of-August standings in years past practically foretells that one of this year's division leaders won't end the season atop their division. The last time all six first-place teams entering September were still on top at the end of the season was 2002.
In the 10 years since, there have been six instances where at least two teams blew a Sept. 1 division lead. Basically, more often than not, there are at least a couple September comebacks.
For whatever reason, September leads were far safer in the first few seasons after playoffs expanded to include a Wild Card in 1995. From '95-'02, 42 of the 48 first-place clubs entering September went on to win their division.
In the next 10 years, however, only 43 of 60 would do so.
There are limits to the "anything-can-happen" mantra. Since the advent of the Wild Card, only one club has come back from a Sept. 1 deficit of more than five games to win a division crown, and that happened 18 years ago, when the Mariners erased a 7 1/2-game deficit to beat the Angels in a one-game playoff and win the American League West in 1995.
The Wild Card is a bit of a different story. The Cardinals' historic 2011 comeback from 8 1/2 games behind Atlanta on Sept. 1 ended up producing the 11th World Series in franchise history.
But it was the Rays' erasing of a nine-game deficit that same year that stands as the largest Sept. 1 margin overcome to win the Wild Card.
The addition of the second Wild Card in each league makes September comebacks even more likely now, simply by the law of averages.
With five playoff spots available instead of four, it's more likely that one of the clubs currently clutching a coveted postseason berth will falter.
The National League Central stands as baseball's tightest division, with the Pirates sitting a game up on the Cardinals as the two clubs close out a three-game series at PNC Park today. The Reds (3 1/2 back) are within that five-game benchmark to consider themselves within striking distance.
The same applies for races in the AL East and the AL West, where the Red Sox and Rangers hold leads, but are being chased by teams within proverbial striking distance.
"At this point of the year, it's about the game at hand," said Rangers manager Ron Washington, whose club led the A's by four games entering September last year, but ended up conceding the division on the season's final day. "It's day-to-day down the stretch. I know we're playing well. To be in the hunt you need to play well."
In the AL Central, the Indians trail the Tigers by 8 1/2 games, making a division comeback historically difficult. But the Tribe also finds itself well within reach of the Wild Card.
The Dodgers' division lead has grown to double digits as pennant races enter September. Media and fans alike have set home-field advantage as a goal for the club -- and a reasonable one at that. But both Skip Schumaker and Nick Punto -- members of that '11 Cardinals team -- know there's still some business to take care of in the NL West.
The team the Cardinals roped in -- the Atlanta Braves -- holds a seemingly insurmountable 15-game edge on Washington. There is no historical precedent for any September comeback of that sort.
A more realistic goal for the Nats would be earning a Wild Card berth. They currently trail Cincinnati by 7 1/2 games in that department.
"We are taking every day as it comes," said Nationals reliever Tyler Clippard. "That's all we can do. We feel very confident in how we are playing, and we'll take it from there. Who knows what is going to happen?"
Clearly, as past seasons have shown us, on Sept. 1, we never do.
AJ Cassavell is a reporter for MLB.com. Follow him on Twitter @ajcassavell.