Britain's Laura Robson threw away a 4-0 lead in the deciding set as she lost to Russian Elena Vesnina in the US Open first round.
Robson is still in the early stages of her comeback from an 18-month absence with a wrist injury and the 21-year-old looked on course for her first grand slam win in two years.
Vesnina, however, battled back from two breaks down in the third set to claim a 3-6 6-3 7-5 victory and she will now play either Andrea Petkovic or Caroline Garcia in round two.
BECOME A WRITER
Do you have what it takes? Sign up today and send over your 250 word test article: http://gms.to/haveyoursay3
For Robson it will be a bitter pill to swallow, especially given the way she dominated stages of the match in the first set and the third.
However she begun to grow frustrated throughout the competition and ultimately crashed out of the tournament at the first hurdle.