Sloane Stephens vowed to "roll over and move on" after suffering a shock first-round defeat to Donna Vekic on the opening day at Wimbledon.

The US Open champion struggled with her serve in windy conditions on No.1 Court and was soundly beaten 6-1 6-3 by the world number 55.

Stephens had not played a competitive match since losing to Simona Halep in the French Open final last month and fell at the first hurdle for the second consecutive year at the All England Club. 

The fourth seed will consider playing a warm-up event before the grass-court grand slam next year, but she will not dwell on making such an early exit at SW19.