Australia’s James Duckworth has replaced Jo-Wilfried Tsonga in the main draw at the US Open after the Frenchman was forced to pull out due to a long-term knee problem.

Tsonga, three times a quarter-finalist at Flushing Meadows, has not played since a semi-final defeat at the Open Sud de France in February. He had knee surgery in April.

The 33-year-old, now ranked 64 in the world, will be replaced in by Duckworth, it was confirmed.

The season’s final grand slam begins on August 27 in Flushing Meadows.