World No.1 Ashleigh Barty has been trampled down at the first hurdle in a U.S Open tune-up at the Rogers Cup on Tuesday as the Australian suffered a shock 6-7(5), 6-3, 6-4 loss to American Sofia Kenin.

Barty, whose number one ranking is in jeopardy, was beaten in just two hours, marking the American’s first victory over a top-five WTA player.

French Open Champion Barty, was playing for the first time since losing in the fourth round at the Wimbledon a month ago. She was not in her best forms which were taken into a full advantage by her opponent Kenin who recording her remarkable victory.

“I think it was a little rust but I think just in general it was just a bit lost. At times I was missing by big margins, which is not something that I am used to or comfortable with but it’s not panic stations. It is my first match on hardcourt in a long time”, Barty told the WTA.

Barty dominated in the first set against Kenin after racing out to a 5-1 lead in the tiebreaker. But world number 29, Kenin took control of the second, carving out a 4-0 lead before a Barty come back to take the match to the next set. She closed out the third set when a misfiring Barty sent a routine forehand long.