It wasn’t long ago that Chevrolet’s Camaro consistently outsold the Ford Motor Company [NYSE:F] Mustang. In fact, the Camaro enjoyed a five-year streak between 2009 and 2014.

But with the launch of its sixth-generation Mustang, Ford suddenly had the edge and has been in front in the sales race month after month since October 2014. Now the Camaro is back in front.

Camaro sales rose 25 percent in September to reach 6,577 units, or 148 units more than the Mustang. But before all you Bowtie fans pop the champagne cork, note that Mustang sales were down 32 percent for the month. Furthermore, the Camaro benefited from aggressive incentives that were around three times higher than the previous month’s average, according to Bloomberg.

2016 Ford Mustang GT

A spokesman for Chevrolet said the strong incentives were to clear out 2016 inventories in preparation for the arrival of the 2017 model. Inventories for the Camaro were at a 139-day supply at the start of September.

It’s not clear why Mustang sales took a dive but it may have to do with a cooling of the new car market as well as buyers holding off in anticipation of an updated model due for 2018. In response to the sales decline, Ford has idled Mustang production this week to reduce inventories. The Mustang had a 71-day supply at the start of September.

The Mustang remains on track to retain the sales title in 2016. Ford has sold 87,258 examples in the U.S. so far this year, down 9.3 percent, while Chevy has sold 54,535 Camaros, down 11 percent. Dodge, meanwhile, has sold 51,186 Challengers in 2016, which is only slightly down on a year ago.