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LIVE: Serena Williams beats Anett Kontaveit 7-6 (7-4) 2-6 6-2 to reach third round
Victory prolongs American's farewell before impending retirement
LIVE: Briton Jack Draper faces Canadian sixth seed Felix Auger-Aliassime in second round
Earlier: Andy Murray beats Emilio Nava 5-7 6-3 6-1 6-0 to reach third round
Britain's Harriet Dart loses 6-4 6-0 to Hungary's Dalma Galfi
Britain's Joe Salisbury and American Rajeev Ram make winning start to their men's doubles title defence
*Williams 7-6 (7-4) 2-6 4-2 Kontaveit
This does not have the feel of a second-round contest.
Kontaveit strikes back with a hot out wide that sees Williams net, and the second seed is able to then bring up a break point.
*Williams 7-6 (7-4) 2-6 4-2 Kontaveit
A well-placed backhand allows Serena Williams to settle into her service game, and she pops away another from mid-court after an enthralling 19-shot rally for 30-15.
Image source, Getty Images*Williams 7-6 (7-4) 2-6 4-2 Kontaveit
That's a brilliant way to finish off a quick, slick love hold.
Kontaveit finds the line with a bullet forehand to stay in touch.
Williams 7-6 (7-4) 2-6 4-1 Kontaveit*
Goodness me. Where has Serena Williams pulled this from?
She could not live with Anett Kontaveit in the second set but the world number two is in huge trouble now.
The six-time champion is closing in on another memorable win in her final tournament.
Williams 7-6 (7-4) 2-6 4-1 Kontaveit*
Serena Williams is unhappy with a net call, but she is able to put that behind her as she reaches 40-0.
Can she avoid any complications this time? She can!
Kontaveit misses and the crowd erupts as Williams moves two games away from victory.
Draper 5-3 Auger-Aliassime*
The last few games have gone with the serve and Jack Draper now needs just one more game under his belt to secure the first set.
This has been a mightily impressive showing from the 20-year-old, while his more experienced opponent, Felix Auger-Aliassime, just doesn't look to have fully settled yet.
*Williams 7-6 (7-4) 2-6 3-1 Kontaveit
Laura Robson
Former British number one on BBC Radio 5 Live
It looked to me like a shaky drive volley, but Serena had enough time to see where Kontaveit was moving.
And now she will get the extra pop on the first serve with the new balls. She has got to take advantage of this.
*Williams 7-6 (7-4) 2-6 3-1 Kontaveit
Incredible!
We have a third successive break as Kontaveit misses with a loose forehand.
Williams 7-6 (7-4) 2-6 2-1 Kontaveit*
A miss from Kontaveit. A smash from Williams. That will be two break points!
*Draper 4-3 Auger-Aliassime
David Law
Commentator on BBC Radio 5 Live
If you brought someone in who doesn't know tennis and asked them who was the sixth seed and who was the world number 53, you would think the seed was Draper.
It is the manner in which he is carrying himself. It looks like he belongs, and Auger-Aliassime just looks stressed.
Williams 7-6 (7-4) 2-6 2-1 Kontaveit*
Serena Williams readjusts her headband and composes herself at the back of the court.
Losing that game is a huge blow, but she has shown she can cause Kontaveit serious problems and she'll look to do just that once again.
Williams 7-6 (7-4) 2-6 2-1 Kontaveit*
Laura Robson
Former British number one on BBC Radio 5 Live
Serena has got to be nervous and you can understand why she was not expected to win this match at all.
People are stressed in the crowd.
Williams 7-6 (7-4) 2-6 2-1 Kontaveit*
Serena Williams drift a backhand into the net. Another break point for Kontaveit...
That's wide from Williams! From 40-0 down, and staring at a 3-0 deficit, Kontaveit battles back.
*Williams 7-6 (7-4) 2-6 2-0 Kontaveit
Kontaveit can't take her chance and a couple of misses put Williams back in charge, but the second seed gets fortunate with a bounce off the net which throws the American off and we return to deuce.
*Williams 7-6 (7-4) 2-6 2-0 Kontaveit
A look of exasperation from Serena Williams as a double fault gives Anett Kontaveit break point.
*Draper 3-2 Auger-Aliassime
Felix Auger-Aliassime is a lucky man. He saves another break point and wraps up his service game on his fourth game point.
Meanwhile Jack Draper - making his US Open debut this year - looks totally at home on the show courts. He doesn't seem to be overawed by the experience at all right now.
*Williams 7-6 (7-4) 2-6 2-0 Kontaveit
Can the 23-time Grand Slam champion deliver on serve to consolidate that break?
It looks like she can as ace number 10 for the match takes her to 40-0.
But a miss lets Kontaveit back in with a third successive point. Deuce.
*Williams 7-6 (7-4) 2-6 2-0 Kontaveit
Quality return! Serena Williams gives herself another break point opportunity as she meets Kontaveit's serve perfectly.
And this time, the game is hers!
Williams 7-6 (7-4) 2-6 1-0 Kontaveit*
Laura Robson
Former British number one on BBC Radio 5 Live
Serena will have to show that she is going to get right on these returns and giving them what they deserve.
Serena has calmed down so much. We were starting to see some frustration, she was moaning a little bit and now there is nothing from her.
Even her grunt is quieter. Just conserving all her energy for her shots.
At this point it is huge. I'm nervous.
Williams 7-6 (7-4) 2-6 1-0 Kontaveit*
And now it's Williams' turn to frustrate Kontaveit in this game as she brings the second seed back from game point...
A second chance passes Kontaveit by too as she overhits a forehand.
Tense moments.