Serena Williams has "promised" her fans she will do better at the US Open after surviving a second-round scare against wildcard Caty McNally on Wednesday.
World No 8 Williams, who captured the first of her six US Open titles two years before her 17-year-old opponent was born, battled to a 5-7 6-3 6-1 win over her fellow American to keep alive her hopes of securing a record-equalling 24th Grand Slam title.
Williams spent the first half of the match trying to find her rhythm but when she did she was off to the races, but she eventually improved to 38-0 in the first two rounds at Flushing Meadows.
"I think she really came out and played well, she showed no fear, she had nothing to lose and she played like it," said a relieved Williams.
"It's refreshing, and it's a different game. I don't get to play players like that too often.
"I knew I could get better, I tried to let Serena come through a little bit. In the first set she was picking out my wide serve, but I have two other serves so I tried them.
"I survived tonight. I'm not too pleased with the way I played at all. Serena you made way too many errors. But I'm still alive and I'll do better, I promise."
The only time Williams was beaten as early as the third round in New York was in her tournament debut all way back in 1998 when she was just 16.