So Keys will play Vandeweghe tomorrow night, a much tougher proposition than Kanepi; I've no idea who might win that, but do join me to find out!
Madison Keys - Kaia Kanepi
US Open women - 7 September 2017
US Open – Follow the Tennis match between Madison Keys and Kaia Kanepi live with Eurosport. The match starts at 07:00 on 7 September 2017. Our live coverage lets you follow all the key moments as they happen.
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Keys 6-3 6-3 Kanepi
Kanepi loses her balance on the baseline, hitting long as a consequence and allowing Keys 30-all. Then she goes long with a forehand, and Keys has matchpoint! Kanepi goes wide with her first serve but her second is good, securing her deuce with the help of two big forehands. She can't close though, a huge forehand pegging her back, and a double fault, only her second of the match - Keys has none - gifts a second matchpoint. And this time she takes it! A backhand clips the line, Kanepi goes wide, and we hear a squeal of excitement! For the first time since 1981, we have four Americans in the semye-final of the US Open!
Keys 6-3 5-3 Kanepi
Keys gets to 40-0 with the help of two high-kicking first serves; think Stefan Edberg. She holds easily, to 15, and needs just one more game to move on.
Keys 6-3 4-3 Kanepi
Keys turns it up again, chasing down to the net to punish a forehand for 0-30. But Kanepi's a gamer, and muscles four points in a row to stay in the match. Her problem is how she goes about breaking.
Keys 6-3 4-2 Kanepi
Keys' first serve percentage has calmed down in the second set, but Kanepi just doesn't have the game to take advantage. She does, though, get to 40-30 before a serve down the T has her stretching to send a return plenty wide.
Keys 6-3 3-2 Kanepi
At 15-0, Keys whips a lovely backhand pass cross-court; it was easier to go down the line, but such is her confidence she just did what she felt. A double fault follows, and seconds later it's 15-40. Kanepi, though, saves both and closes out the game in short order. Well played her.
Keys 6-3 3-1 Kanepi
Keys and Vandeweghe will be an interesting semye; both have big power, neither has staying power - at least, we haven't seen it yet. You'd not back them over either of the other two, but they'll be playing each other and one will have to get through. Another easy hold.
Keys 6-3 2-1 Kanepi
Better from Kanepi; in commentary they say she's not panicked, but you could read it that she's happy to be there and knows she's going to lose.
Keys 6-3 2-0 Kanepi
This is not going to last much longer. Keys rattles through a hold to 15, slotting in her sixth ace, and Kanepi can't stay in the rallies long enough to exert pressure.
Keys 6-3 1-0 Kanepi
Big game for Kanepi, this. And she starts it well enough, but Keys then outhits her from the back for 15-all and stomps into a murderous forehand down the line for 30-all. Kanepi then goes long, but what a shot she produces to save break point, a forehand which clips the baseline. They then go backwards and forwards to advantage and deuce, Kanepi saving another break point with a serve out wide and a big forehand ... but it only delays the inevitable. Well, the inevitable in that it happened, which I think makes it philosophically inevitable. Keys breaks!
Keys 6-3 Kanepi
Kanepi isn't forsaking this set without a fight, piling into a return at 30-all. But it's long, a big serve down the middle has her on the stretch, and she can't control the return. Keys yelps a "Come on!" and she knows this match is hers to win.
Keys 5-3 Kanepi
Keys is absolutely full of it, leathering and stroking her returns at the same time. She's quickly up 0-30, but Kanepi calmly closes, only to be diddled again by a wonderful return ... but Keys ambles into the net, can pat the ball wherever she likes, and hits the net instead. They end up playing deuce, and Kanepi closes out. Keys will have to serve for it.
Keys 5-2 Kanepi
Keys serves her fifth ace of the match in the process of holding to 15. She's looking really good, much as she's being allowed to - Kanepi just doesn't quite have the game to compete.
Keys 4-2 Kanepi
Three short points for get Kanepi back into things, but Keys then finalges one point before lazily mullering a return to get us wondering. Her power is something else. But Kanepi doesn't panic and quickly closes out.
Keys 4-1 Kanepi
A comfortable consolidation for Keys, whatever that means. Pint of Comfortable Consolidation please.
Keys 3-1 Kanepi
I really like how Kanepi is turned out here, none of this sponsored nonsense, just a plain black singlet that does all the necessary. But it's not going to help when she finds herself 15-40 down, and Keys picks a big forehand return which allows her to control the rally and register the first break of the evening!
Keys 2-1 Kanepi
Kanepi edges her way to 15-40, and looks to have a chance of a pass with Keys caught at the net. But she hits the net post, before Keys sends down a kick serve that's too good. Kanepi is a real poowerhoose, and forces Keyes to save another break point, but eventually the server prevails. She knows she's in a match, but.
Keys 1-1 Kanepi
Kanepi responds well with a love game of her own. Last season, she nearly gave up the jig; she injured her shoulder and wondered if it was worth it. But she read some books, chucked some discus, and here we are!
Keys 1-0 Kanepi
A relaxing settler for Keys, who rolls through a love hold in a cavernous-sounding Ashe. It's almost as though people buy tickets to tell their mates they've bought tickets.
Off we go, Keys - sorry, I mean "Maddie" to serve.
Our players are knocking up, and our camera focuses on Madison Keys who is aiming to make it a USA USA USA clean sweep of semi-finalists. I guess I'd love to see Venus win, but then I'd also love to see Sloane Stephens win. I would not love to see CoCo Wandeweghe win.
As for Kanepi, you'd expect that for a qualifier to get to here, she'd have to have beaten at least one someone. But not even one low seed, which is remarkable; good luck to her. Hard to see how she gets out of this one, though.
She's a funny one, Madison Keys, capable of brilliance and uselessness, often in the same game. It's getting to the point with her; the point at which we find out if she's actually going to amount to anything. Can she find the consistency and big-match temperament?
Evening all, and welcome to yet more wonderful tennis. We kick off tonight with Madison Keys, the ever-promising American, against Kaia Kanepi, the Estonian qualifier.