Australia's 2001 US Open champion Lleyton Hewitt on Tuesday withdrew from this year's renewal with a foot problem which has wrecked his summer of tennis.
The 30-year-old, who won the title a decade ago and got out on one of the last flights leaving the city before the terrorist strikes the next day, lost a first-round match on Monday at the ATP event here.
In his usual style, the two-time Grand Slam champion gave no indication of his intentions, saying he would need "a lot of practise and a lot of treatment" before the start of the season's final major on Monday.
Hewitt underwent surgery on his foot in the spring and has never returned to court pain free. He has not reached the second week of a major since Wimbledon, 2009.