Great rally, but it's Madison Keys who comes out on top!

Katie Swan might feel she should have won that, sauntering to the net and facing a volley to win it, but she leaves it in a gettable spot for Keys and the American swoops with a sweeping forehand winner.

Double fault from Katie Swan, and Madison Keys jumps on the next point to bring up a third chance to break early in this second set.

That's better from the world number 290, aggressively thumping a forehand to Keys' backhand side from mid-court. The American tugs a backhand wide and both break points evaporate. Deuce.

Katie Swan finds herself squatting down to try and deal with a Madison Keys return that's struck straight at her feet. Swan the leaks a forehand winer and it brings up two early break points for the American.

The first is saved as Swan gets Keys on the run and the American trickles a low forehand into the net.

But the British player can't deal with a fierce serve on the next and Keys takes the opening set.

A string of snappy serves from Madison Keys and Katie Swan bats a leaping effort into the bleachers.

Three set points.

Jodie Burrage's Wimbledon debut starts with a challenge as she falls a set down to American Lauren Davis.

While over on Court 17 American Danielle Lao leads Katie Boulter 4-2 in the opener. The winner of that one takes on world-number-four Aryna Sabalenka, who won earlier today.

It's all been happening at the end of the second set between Tiafoe and Tsitsipas.

Tiafoe broke the Greek's serve at the third opportunity for a 5-4 lead and the chance to serve for a two-set lead, only to find himself 15-40 and three break points down in the next game.

Somehow Tiafoe, despite a heavy fall on the way, manages to save all three before turning things around and taking the set...

A huge challenge for third seed Tsitsipas to turn this around now.

Jo Durie
Former British number one on BBC TV

This is definitely the day to go for the space.

Get your opponent running and thinking about when they have to stop!

Superb hold from Katie Swan. She digs in and forces Madison Keys to serve it out.

Big serve, right down the T from the British world number 290, but Katie Swan can't do anything about a ferocious backhand winner down the line that flies right out of Madison Keys' sweet spot. Deuce once more.

Nice from the British qualifier, rifling down a big serve and then tickling a forehand winner over from close range on the bounce, with Madison Keys beaten.

But the next is leaked into the tramlines and the 22-year-old then pokes a volley wide. Deuce.

Katie Swan is forced behind the baseline and cups a forehand into the tape from deep, but a leaping, swerving second serve towards the frame of Madison Keys gets her off the mark.

Swan then goes scampering to the net and a neat volleyed combo makes it 30-15.

Madison Keys doesn't mess around between points. Her serve is flying, and it's just bosh, bosh, bosh, doesn't want to lose the mark, like a good darts player. The American quickly holds to love and Katie Swan finds herself serving to stay in the opening set.

A big, big hold for Katie Swan after slipping 15-40 behind. That should steady the nerves.

Flat-batted out the back of the court by Madison Keys from a punchy Katie Swan serve. She must be listening to Jo Durie... deuce.

Jo Durie
Former British number one on BBC TV

Swan has to go for it more with her first serve. I think it's worth the risk if you know your second serve is going to get thumped.

Keys jumps all over the Swan second serve to move to 0-30, before dragging a backhand wide. The American is eyeing winners...

Jo Durie
Former British number one on BBC TV

I love the easy power of Madison Key's serve.

You see the racquet snap as it goes through.

The Williams sisters used to chuck racquets - it's really satisfying!