London: Stan Wawrinka became the latest star to suffer a shock exit from Queen's Club as the French Open champion was beaten 7-6 (7/4), 7-6 (13/11) by South Africa's Kevin Anderson on Wednesday.

Just 24 hours after Rafael Nadal's first round defeat against unheralded Ukrainian Alexandr Dolgopolov, it was Wawrinka's turn to succumb to an unexpected loss at the Wimbledon warm-up event in west London.

Stan Wawrinka became the latest star to suffer a shock exit from Queen's Club as the French Open champion was beaten 7-6 (7/4), 7-6 (13/11) by South Africa's Kevin Anderson on WednesdaySwitzerland's Stanislas Wawrinka returns to South Africa's Kevin Anderson during a second round match at the ATP Aegon Championships tennis tournament at the Queen's Club in west London on Tuesday. Pic/AFP

The Swiss second seed had swept through his first round clash against Australian Nick Kyrgios in just 49 minutes as he looked to follow his memorable final triumph over Novak Djokovic in Paris with his first ever grass-court title. But, in the second round, Wawrinka couldn't find a way to subdue the big-serving Anderson, who fired down 22 aces en route to his first win over a top five ranked opponent this year.

Wawrinka had been hoping to extend his winning run to nine matches, but the towering 6ft 8in Anderson had won their last three meetings, all in 2014, and he proved a thorn in the 30-year-old's side again.

A hard-fought first set looked to have swung Wawrinka's way when he secured two set points at 6-5, only for the Swiss to let Anderson off the hook as the 29-year-old raced through the subsequent tie-break.

The superstitious Wawrinka was still wearing his 'lucky' pair of garish red, white and grey checked shorts that caused a stir during his triumphant run in Paris, but his fortune took a turn for the worse in the second set.

Anderson had brought Lleyton Hewitt's Queen's farewell to a premature and painful end after saving a match point during his first round victory against the four-time champion. He claimed a more high-profile scalp on this occasion thanks to a dramatic second set tie-break which saw Wawrinka save five match points and Anderson rescue two set points before the South African finally sealed his win.

In the quarter-final, Anderson will play either world number 79 Dolgopolov or Spain's Guillermo Garcia-Lopez.

Earlier, French seventh seed Gilles Simon ended Thanasi Kokkinakis's emotional Queen's Club debut with a 6-4, 6-2 second round victory over the Australian teenager.

Kokkinakis has spent much of this week in the air after making the long flight back to Australia to spend a day at home with his sick grandmother before an unscheduled return to Queen's.

The highly-rated world number 70 had jetted back to Adelaide to be with his family after the French Open, only to discover on landing that he had been offered a wildcard entry into the Wimbledon warm-up event in west London. Kokkinakis got back on a plane, shrugged off the inevitable jet-lag and captured his first tour-level win on grass on Tuesday when he came from a set down to defeat France's Jeremy Chardy.

But the 19-year-old, one of only four teenagers in the top 100, can now take a well-earned rest and catch up on some sleep after being brushed aside by Simon.

Next up for world number 13 Simon in the quarter-finals will be the winner of Wednesday's meeting between Canadian third seed Milos Raonic and France's Richard Gasquet.