WINSTON-SALEM, N.C. — Defending champion John Isner and top seed Jo-Wilfried Tsonga of France both won Tuesday in the second round of the Winston-Salem Open.

WINSTON-SALEM, N.C. — Defending champion John Isner and top seed Jo-Wilfried Tsonga of France both won Tuesday in the second round of the Winston-Salem Open.

The third-seeded Isner, the highest-ranked American (10th) in the world rankings, was pushed to three sets before beating Slovakia's Martin Klizan 4-6, 6-3, 7-5.

Tsonga, the highest-ranked player (sixth) in the final hard-court tournament before the U.S. Open, beat Brazil's Thomaz Bellucci 6-3, 7-6 (7-2).

Isner, who was born in nearby Greensboro, N.C., showed the effects of a two-week layoff, coming out sluggish against Klizan.

The left-hander broke Isner's serve in the opening game of the first set, and kept him scrambling with his groundstrokes.

However, Isner eventually picked up his game, serving 13 aces.