Juan Martín del Potro, the seventh-ranked tennis player in the world, won his third Citi Open title—and first since 2009—on Sunday when he beat John Isner in three sets at the William H.G. FitzGerald Tennis Center in Rock Creek Park.

For del Potro, the 24-year-old Argentinian, the win was a bounce back from a semifinal loss to Novak Djokovic at Wimbledon last month. On Sunday, del Potro beat Isner 3-6, 6-1, 6-2 in less than 90 minutes to take his first tournament since that five-hour epic against the world No. 1.

Despite taking the first set, Isner, the world No. 20, could not keep up in the next two. The 6-foot-9 American, who hits some of the hardest serves in professional tennis, finally wore down after playing nine matches over a span of just 11 days, including a hard-court tournament he won in Atlanta last week.

The title is del Potro’s first in D.C. since he won back-to-back tournaments in 2008 and 2009. (The event was still known then as the Legg Mason Tennis Classic.) Magdaléna Rybáriková, the 39th-ranked player in the world and No. 7 seed in this tournament, won the women’s draw for the second consecutive year.

Mayor Vince Gray attended Sunday’s matches to present the championship trophies.