US Open champion and French Open finalist Sloane Stephens became the first major casualty of Wimbledon 2018 after losing to Donna Vekic.

Stephens claimed her first grand slam at Flushing Meadows in 2017 and was a set and a break up on Simona Halep in the Paris final earlier this year.

However, the grass of Wimbledon has never been a happy hunting ground for the American – apart from her quarter-final appearance in 2013 – and that continued on day one.

Vekic had recorded mixed results heading to SW19 but turned on the style on Number One Court, sending fourth seed Stephens crashing out 6-1 6-3.

Stephens – who also exited in the first round 12 months ago – was quickly under pressure and within 25 minutes she had seen the opening set slip away.

There was more fight in the second but Stephens' serve let her down badly, only holding twice in the match and suffering four second-set breaks as Vekic marched into round two.