Atlanta - Former world No 1 Lleyton Hewitt blasted 10 aces en route to a 7-6 (8/6), 6-4 in over Rhyne Williams in the second round of the Atlanta Open.
The 32-year-old from Adelaide won 78 percent of his first-serve points and had his serve broken just once in the one hour, 47 minute hard-court match.
Hewitt advances to the quarter-finals where he will face Ivan Dodig of Croatia who beat Ricardas Berankis in three sets, 6-1, 6-7 (3/7), 6-3.
Hewitt, who was the number one ranked player in the world in 2001, is seeking his 29th career singles title. His last win came three years ago in Halle.
Williams hammered 18 aces but made four double faults and only saved one of three service break points.
Sixth-seeded American Mardy Fish crashed out of the tournament on Wednesday losing 4-6, 6-2, 7-5 to Michael Russell in a match that was played over two days.
Russell won the first set 6-4 and was behind 2-4 when the second of two rain delays finally halted play on Tuesday night.
First-round winners on Wednesday included Christian Harrison, an American wild-card who needed three sets to thwart Colombian Alejandro Falla 6-1, 6-7 (7/9), 6-2.
Croatian Ivo Karlovic retired after dropping a 6-2 first set to Australian qualifier Matthew Ebden. Ebden will take on South African second-seed Kevin Anderson in the second round.