The ace bounced off the Court 1 backstop as Williams trotted to the net to bid another foe farewell.
The scoreboard said 127 mph, the fastest women's serve ever recorded at Wimbledon. The scoreboard also had Williams winning 6-1, 7-5 Saturday over qualifier Maria Jose Martinez Sanchez.
It was an upset-filled first week at Wimbledon and a rough one for American tennis, but the nonconformist Williams sisters ignored both trends. Four-time champion Venus and two-time champion Serena won three matches each without dropping a set.