Samantha Stosur is hoping her "bittersweet" US Open experience will serve as the springboard to a third straight appearance at the prestigious season-ending championships.

Stosur returns to action at the big-money Japan Open this week feeling refreshed and focused after a relaxing week home in Australia following her quarter-final heartbreak at Flushing Meadows.

The Queenslander's title defence in New York ended with a third-set tie break loss to world No1 Victoria Azarenka.

That Azarenka went on to lose the final to Serena Williams in similarly gut-wrenching fashion only added to Stosur's frustrations.


But the world No9 said making another Grand Slam quarter-final and pushing the game's top-ranked player was the morale booster she desperately needed after a poor grasscourt campaign at Wimbledon and the London Olympics.

"To lose by the smallest of margins was not easy but it was also still rewarding that within a couple of weeks I really turned my form around and was playing well and was full of confidence," said Stosur.

"It was bittersweet in the end. It was good for a lot of reasons, but obviously the end result just wasn't quite what I wanted."