ATLANTA (AP) — Second-seeded John Isner beat Slovakia's Lukas Lacko 7-5, 6-4 on Friday to reach the BB&T Atlanta Open semifinals.

Seeking his fourth Atlanta title in five seasons, the big-serving Isner will face third-seeded Gilles Muller of Luxembourg. Muller beat American Tommy Paul 6-3, 6-1.

Isner won the Hall of Fame Open on Sunday in Newport, Rhode Island, for his 11th career title — all at the ATP World Tour 250 level. The 6-foot-10 former University of Georgia star lost to Nick Kyrgios last year in the final at Atlantic Station after winning the hard-court event the previous three seasons.

Fifth-seeded Kyle Edmund of England beat top-seeded Jack Sock of the United States 6-4, 6-1 in the night match. Edmund will face fourth-seeded Ryan Harrison, a 6-1, 6-2 winner over Christopher Eubanks in an all-American match.