(Photo by Katherine Frey/The Washington Post)

At the risk of jinxing it, the Washington Nationals should see postseason play this season. They have a seven game lead on the Atlanta Braves for the NL East division title and have been in control of their own destiny for some time now.

The Nats’ magic number to clinch is 18. That means any combination of Washington wins and Atlanta losses will assure the Nationals’ the NL East crown.

So when is this most likely to happen?

Here are the remaining games for the Nationals and Braves, including today’s games.


Using Bill James’s log5 method to calculate the estimated win probability for each game, with team strength based on the 2014 Pythagenpat win percentage found at Fangraphs, we can run the remaining season 10,000 times and see when it is most likely for the Nats’ magic number to be zero.

For example, the Washington Nationals have a current Pythagenpat win percentage of 0.588, while the Dodgers are at 0.550. That means the Nationals have a 53.9 percent chance of winning this game. The Braves (0.513 Pythagenpat) face the Phillies (0.457 Pythagenpat), so Atlanta has a 46.3 percent chance at a win. If they Nats win and the Braves lose, the magic number becomes 163- Nats wins – Braves losses = 16. If both teams win, the magic number is 17. And so on. Do this 10,000 times for each game and we can get a good sense at how the remainder of the season will shake out. Here is how likely the Nats are to clinch in each of their remaining games.

The Nationals are most likely to clinch September 18 through September 21, when they have their road trip in Miami. Their best chance to clinch at home comes against the Mets, either on September 23 or 24. Plan accordingly.


Note: A previous version of the charts had the incorrect probability for Game # 152 against Miami. This has been fixed.