Evening all, and welcome to some Mertens-Keys!

So there we go; the more I think about it, that was an odd match. Keys really felt the pressure, yet any time there was any serious pressure, she raised her game. Riddle me that. anyway, we're done here - join me for Federer-Tiafoe, though, which starts shortly.

Every time Mertens has had a sniff Keys has found something, and she loops a forehand long to give Keys match point. Mertens goes long with the return, and that's that! Keys looks very chuffed, and I'm not surprised - she was really nervous out there, and Mertens was difficult first-round opponent. Keys could do some damage here, if she gets a hold of herself - she plays Maria or Kratzer next.

Mertens quickly breaks back - she won't let Keys get away - and Keys then dictates the next point with some decent hitting, only to reject opportunities to come in and punish a drive volley winner, before going long. A winner down the line then gives Keys 5-5, but an unforced error on the forehand gives Mertens set-point! Her first serve is long, and then a huge forehand into the corner from Keys saves it! What a shot that was!

Mertens cedes the first mini-break when she opens space for a backhand winner down the line, only to net, and Keys quickly consolidates. She looks solid as they change ends.

Keys has just raised things these last ten minutes and quickly claws back to 15-all after Mertens takes the first point of the game. But a double fault allows doubt in, and when Mertens opens her shoulders into a forehand, Keys nets and will face to break-back points. She plays a lovely rally too, but then doesn't kill a volley and finds herself lobbed at the net! A breaker it is!

You can hardly hear the ball on the racket, such is the racket on the roof, but Keys isn't arsed, climbing into a backhand for 0-15. But when the opportunity presents itself again next point, she nets, only for a double fault to give her a sniff. And it's all she needs; she seizes the initiative, nailing the break with a forehand volley, and in 90 seconds will serve for the match!

A net-cord gets Keys ahead in the game and she powers through a love-hold of her own. She'll fancy herself if it comes to a breaker.

Mertens in 77% on first serves this set and a second love-hold of the match means that Keys will shortly serve to stay in the set.

An easy hold for Keys, hitting the ball really cleanly and moving well. If she can just find a tad more consistency with her returns, this will soon be over.

At 40-30 Mertens sends down her fourth double of the match; if Keys can seize the half-chance, that might be that. And she cracks a return at Mertens' feet, but misses an opportunity to hit a winner, hitting the net instead, then again.

Tin of Monster just out of shot.

At 30-30 Keys drops a backhand short and Mertens races into the net, only to hit it with her backhand. That was a chance, but then a net-cord flicks the ball over Keys' racket for a winner, eliciting a shriek of anguish. Again, though, Keys finds what she needs, coming in off a forehand topspin cross-court, but still managing to return to that flank for a volley winner. Very nice, and I wonder if we'll see a break next.

At 15-30 Keys reads two shots in a row and off the second a lovely volley across the net raises two break points; she can't take either, dumping two returns into the net and not even near the top of it. Merterns then cleans up to edge in front in the set again.

You can hear the hiss of rain as Keys serves, and again her backhand runs her into minor strife at 30-15. They end up playing a deuce after Keys saves a break point, and then she seals the game with an almighty backhand cross-court. Basically, whenever she's pushed she finds something with which to respond.

Mertens is wearing the most terrific shade of shocking pink, which I do not say because she is a woman but because it is too terrific a shade to ignore. Anyway, with the rain caning down on the roof, she holds easily.

Keys finds herself having to play a deuce, but judges a tricky touch volley beautifully to get on the board in this set, praising herself accordingly thereafter.

Mertens needs to find better angles than Keys, because she can't attack with the same ferocity from the baseline. She can't though, and a classy backhand volley from keys gets her to deuce before a botched overhead gives Mertens game point, which she takes.

Finally Keys is chilling, and she serves out to love in impressive fashion. She looks to have just too much for Mertens.

At 0-15, Keys hits a brilliant forehand cross-court pass on the run giving her a chance of sorts; naturally she follows up with a wild forehand. But Mertens then nets, and Keys now has two break points. She takes the second, with the help of a net cord setting up a forehand winner - but only once Mertens had failed to put away a volley. Keys will now serve for the set.

Mertens won't let Keys settle, and from 40-15 a forehand winner and a double fault take us to deuce. So Keys takes some pace off her serve which works, but then she hits a forehand into the net. She really needs to relax, as I keep saying. Still, she now leads 4-3.

Er, not sure that's how this works.

Keys is hitting with better length as well as power now; Kim Clijsters is wearing a black turtle neck and a black leather waistcoat. Seriously. Anyhow we end up at deuce before two backhand errors from Keys hand Mertens the game.