Though the Class AA Harrisburg Senators fell out of first place Thursday night, they could make September even busier for the Nationals‘ farm system. They’re two games up with 11 to play in a bid to become the organization’s fourth playoff team out of six domestic clubs this season.

Potomac and Hagerstown, the Nationals’ two full-season Class A affiliates, each won first-half titles to clinch postseason berths and lead their divisions in the second half, as well.

The rookie-level Gulf Coast League Nationals are also playoff-bound and by a large margin. The GCL team has the best record in all of the minors at 46-8 (.852), giving it a 23-game lead over the Marlins affiliate with six games left. Top pitching prospect Lucas Giolito has moved on to the New York-Penn League, where he won his first start with Auburn, but the Viera, Fla.,-based club still has won four in a row.

As for the Senators (69-62), they have 11 games remaining and are a half-game behind Erie (69-61), two ahead of Richmond (67-64) and 2 1/2 ahead of Bowie (66-64). The top two teams in the Western Division race will play each other in the postseason. Harrisburg took two of three at Giants-affiliated Richmond earlier this week and will be back at the Diamond with a four-game set to close the regular season.

“The biggest thing is that they’ve come together as a club,” Harrisburg Manager Matthew LeCroy said in Richmond earlier this week. “Guys have rallied and bought into the chemistry that we have. That, and our pitching has been really good no matter who we’ve had.”

The Senators lead the Eastern League with a 3.43 ERA while allowing the fewest walks and striking out the third-most batters. Right-hander Nathan Karns, who made three starts with Washington this season, ranks fifth among qualifying pitchers with a 3.32 ERA and is tied for second with 140 strikeouts. Left-hander Robbie Ray and right-handers A.J. Cole, Taylor Hill and Matt Swynenberg are also part of a strong rotation, and right-hander Aaron Barrett is second with 25 saves.

LeCroy’s lineup has received an injection of speed with the promotion of left fielder Billy Burns from Potomac and the return to health of center fielder Brian Goodwin. Burns was 51 for 56 on stolen base attempts in the Carolina League and is nine for 11 with Harrisburg.

“When Goodie was out, Burns added a dynamic at the top of the order,” LeCroy said. “Now it’s nice to have the two of them together.”