American 15-year-old Coco Gauff beats Russian teenager Anastasia Potapova 3-6 6-2 6-4 in US Open first round
British number one Kyle Edmund loses 3-6 7-6 (7-1) 7-5 5-7 6-2 to Spain's Pablo Andujar in the US Open first round
Top seed and defending champion Naomi Osaka comes from behind to beat Russia's Anna Blinkova in her opener
Three-time US Open champion Rafael Nadal faces Australia's John Millman at 00:00 BST
Wimbledon champion Simona Halep beats Nicole Gibbs
Use audio icon at the top of the page for BBC Radio 5 Live Sports Extra commentary
*Osaka 6-4 6-7 (5-7) 3-1 Blinkova
Chanda Rubin
American former world number six at Flushing Meadows
This would certainly be perhaps the most comfortable lead for Osaka in this match. She scraped through turning that first set around; throughout the second set it was tight, she never really got up a big lead. Right now feels like it's a little bit more space to consolidate and go up 4-1.
Edmund 6-3 4-4 Andujar*
A glorious forehand down the line brings the game to deuce.
Edmund is not giving up on this game.
Edmund 6-3 4-4 Andujar*
Edmund wins his 11th out of 12 net points he's faced with a backhand volley.
30-30.
40-30.
*Osaka 6-4 6-7 (5-7) 3-1 Blinkova
The first break point goes begging as Osaka can only pull her backhand into the net but she doesn't say no to the second one.
Now, can the top seed put this match to bed?!
Osaka 6-4 6-7 (5-7) 2-1 Blinkova*
Chanda Rubin
American former world number six at Flushing Meadows
I think it would help, in this set, for Osaka to be serving first, after having held serve, she can relax a little bit more, take a few swings, maybe create some additional opportunities and give herself some breathing room here.
Image source, Getty ImagesEdmund 6-3 4-4 Andujar*
Can Andujar now hold?
A double fault in the first point won't help.
Osaka 6-4 6-7 (5-7) 2-1 Blinkova*
The top seed races to a 30-0 lead but is then chasing as she hooks a forehand long.
And then suddenly, she has two break points. What is going on!?
Edmund 6-3 4-4 Andujar*
But he fails to save the third as Andujar has him on a string before delivering the killer blow at the net.
*Edmund 6-3 4-3 Andujar
He saves a second by opening up his body at the net to slap away a forehand winner.
Image source, Getty Images*Edmund 6-3 4-3 Andujar
Edmund saves one. Just about.
Osaka 6-4 6-7 (5-7) 2-1 Blinkova*
Osaka sees off two break points (!!) and then slams an ace down the T. She holds when Blinkova overcooks a forehand.
Phew! There are only six defending champions who have lost in the first round - Osaka won't want to make it seven...
*Edmund 6-3 4-3 Andujar
Edmund is experiencing a dip.
Andujar's baseline returns have been brilliant in this game and he's got a triple break-point as the Briton makes yet another error.
*Edmund 6-3 4-3 Andujar
What's this? Andujar is 40-0 on his serve!
Edmund sees to it that it's not a love game by plonking a backhand winner down the line.
The Spaniard keeps his nerve to hold.
He's hanging on.
*Osaka 6-4 6-7 (5-7) 1-1 Blinkova
Chanda Rubin
American former world number six at Flushing Meadows
What a moment from a player like Blinkova. She's had a couple of top ten times, but this is a completely different level, trying to take down a world number one.
Image source, Getty ImagesEdmund 6-3 4-2 Andujar*
A great angled forehand return from Pablo Andujar makes life a little bit more difficult for Edmund.
40-30.
Andujar then goes long from the baseline.
Edmund remains a break up.
*Edmund 6-3 3-2 Andujar
This is a really good service game from Edmund so far.
Like a boxer just utilising the jab, the Briton punches Andujar with forehand after forehand before the Spaniard admits defeat.
30-0.
Osaka 6-4 6-7 (5-7) 1-0 Blinkova*
The defending champion comes through this game smoothly - boxing it off with a one-two punch.
Osaka 6-4 6-7 (5-7) Blinkova*
David Law
BBC Radio 5 Live Sports Extra tennis commentator
We're going all the way here! Osaka had a real battle on her hands here. It's possible she could be going out here because Anna Blinkova is playing fantastic tennis.
*Edmund 6-3 3-2 Andujar
15-30.
Edmund then pulls out a magical forehand from his box of tricks. The crowd acknowledge the effort.
Andujar goes on to hold through.
Osaka 6-4 6-7 (5-7) Blinkova*
There it is. Blinkova gets the mini-break and this time takes the second set point. Osaka is going to have to go to the wire here.
Image source, Getty Images