Stosur bundled out of US Open

Sam Stosur's bid for a second US Open crown has come to a halt with the Australian star eliminated by Italian Flavia Pennetta during a straight sets loss in the fourth round.

The last singles player to carry the Australian flag failed to find her form from the opening three rounds, falling 6-4, 6-4 on Arthur Ashe Stadium.

It was a disappointing end for Stosur, who won the US Open in 2011, and rated a genuine chance of claiming her second grand slam crown at Flushing Meadows.

The 31-year-old was eyeing a quarter-final against either Czech fifth seed Petra Kvitova or Sydney-born Brit Johanna Konta had she of beaten Pennetta.

The loss continued Stosur's wretched run against Pennetta, who she has never beaten.