Welcome to September. The final complete month, before we know who’s headed to the playoffs and who will be watching from home. We’ve been keeping track all year of what it means to hold a division lead entering any month, and there’s no question that it’s of more importance now than ever.

If your favorite team isn’t leading now but still has postseason aspirations, they’d better figure it out soon or be vying for a Wild Card spot.

Let's take a look at what it means to be in first place in a division and what the playoff field may look like. Note, all stats below exclude the shortened 2020 season and instead look at full seasons for the impact and postseason implications.

• Division standings | Wild Card standings

What it means to be in first place (or not be there)

Since 1996 -- the first full season with at least one Wild Card in each league -- 125 of 156 eventual division champions held at least a share of their division lead entering Sept. 1. That’s 80 percent of division winners.

There has not been a season since 1996 when none of the division leaders entering September went on to win their divisions that year. In other words, history tells us that most of the six current leaders -- the Orioles, Twins, Mariners, Braves, Brewers and Dodgers -- will win the division. But not necessarily all of them.

(And yes, Astros fans, the team is right there in the AL West. It’s a virtual tie, but because Houston’s winning percentage is slightly lower, officially, it isn’t a true tie. But we see you.)

For those with comebacks in mind, the Elias Sports Bureau tells us that the largest division lead entering September for a team that did not win that division is 7 1/2 games by the 1995 Angels, who missed out on the playoffs entirely when the Yankees won that year’s Wild Card and the Mariners won the division.

Largest division lead Entering September, did not win division (Since 1969)

1995 Angels: 7 1/2
1978 Red Sox: 6 1/2
2006 Tigers: 4 1/2
1969 Cubs: 4 1/2

What about eventual World Series winners? Since 1996, 17 of the 26 World Series winners, again, excluding 2020, led their divisions entering September.

Tight AL West race

As alluded to above, the Mariners and Astros are in a virtual tie atop the AL West. And the Rangers are just a game behind. That means the top three teams in the AL West are all separated by a game or fewer.

This is the third time since divisions began in 1969 that three teams in the same division were within a game or fewer of the lead entering September, joining the 1980 NL East and 1969 NL West. A historic finish is on the horizon.

The AL East

We’ve covered the fact that the AL East could be historically strong, but it bears a recap here. The division has a combined .556 winning percentage, which would be the highest by a division in a single season. The current record for a five-team division? .541 by the 2022 AL East.

Four of five AL East teams are above .500, with the Yankees four below. If you’re curious, the latest into a season that an entire division has been above .500 was the NL East in 2005, according to the Elias Sports Bureau. All five teams were over .500 through Oct. 1, the second-to-last day of the season. The Nationals then lost their finale to finish 81-81.

This year’s leaders

Of this year’s current division leaders entering September, each has had at least a share of that lead entering September at least once prior since 2021, except the Orioles and Mariners. Baltimore was last in this spot in 2014, and Seattle in 2001. The Twins, Braves, Brewers and Dodgers have each won their divisions at least once since 2019. The Orioles last did so in 2014, the Mariners in ‘01.

What’s next?

There’s no longer plenty of baseball to be played. The baseball that’s left, it’s going to be among the highest of stakes. This is an entire month and a day of important games. If your team is currently in playoff position, there’s a lot of evidence for optimism. And if your team isn’t, just know that we’ve seen plenty of September comebacks, all things considered.