Welcome to September. Though the regular season ends on October 5 this year, there’s no question that this month will be pivotal. 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, which each league has one more of this year.

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.

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 -- 120 of 150 eventual division champions held at least a share of their division lead entering September 1. That’s 80 percent of division winners.

There has not been a season since 1996 where 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 Yankees, Guardians, Astros, Mets, Cardinals and Dodgers -- will win the division. But not necessarily all of them.

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, 16 of the 25 World Series winners, again, excluding 2020, led their divisions entering September.

History worth noting

The Dodgers lead the NL West by 18 1/2 games. That’s tied for the fifth-largest lead entering September since divisions began in 1969. No team has led by that much entering September since Cleveland in 1999. In other words, it’s been a while.

Largest division leads entering Sept. (since ‘69):

1995 Cleveland: 21 1/2 games
1999 Cleveland: 20 games
1980 Royals: 20 games
1986 Mets: 19 games
2022 Dodgers: 18 1/2 games
1975 Reds: 18 1/2 games

In New York, both teams lead by at least three games in their respective divisions – the Yankees by six and Mets by three. But the Yankees, who once led by 15 1/2, went 10-18 in August, a .357 win percentage that was their worst in a calendar month (min. five games) since September 1991 (9-19, .321), while the Mets have seen the Braves turn a once-10 1/2-game deficit into just three games.

It’s only natural to wonder what the history might be.

Just seven teams since divisions began (1969) have had a 10+ game division lead, then had another team either tie or overtake them for 1st at some point, according to Elias:

2019 Twins* – largest lead: 11 1/2 games
2012 Yankees* – 10
2006 Tigers** – 10
1995 Angels – 11
1993 Giants – 10
1979 Astros – 10 1/2
1978 Red Sox – 10

*won division

**made playoffs as Wild Card

To be clear, the ‘19 Twins and ‘12 Yankees are on the above list because this is teams to tie for or lose their lead at any point – so, even if either team loses its lead and eventually regains it.

Thus, the largest blown lead in the divisional era by a team that did not go on to win that division is 11 games. If we expand prior to the divisional era, and look at league leads, the largest blown lead was the 1951 Dodgers’ 13-game lead. You may recall that the Giants won the pennant that year.

Of course, that’s also the difference worth noting here, which applies to the 1993 Giants, ‘79 Astros and ‘78 Red Sox above as well. There are three Wild Card spots per league this year – a far different type of field.

What’s next

There’s no longer plenty of baseball to be played. The baseball that’s left is going to be among the highest of stakes. This is an entire month and three days 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.