Boulter holdspublished at 16:42 British Summer Time
*Kessler 6-3 3-6 1-1 Boulter
Superbly done from Boulter. Two more mahoosive serves help her to a hold.
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British number one Jack Draper beats Brandon Nakashima 6-4 5-7 6-4 to reach Queen's last four for first time
Top seed Carlos Alcaraz beats Arthur Rinderknech 7-5 6-4 to reach semi-finals
GB's Jacob Fearnley beaten 7-5 6-2 by Jiri Lehecka in last eight
Joe Rindl, Gary Rose and Grace Wheeler
*Kessler 6-3 3-6 1-1 Boulter
Superbly done from Boulter. Two more mahoosive serves help her to a hold.
Kessler 6-3 3-6 1-0 Boulter*
Break point saved. Unreturnable serve.
Kessler 6-3 3-6 1-0 Boulter*
Kessler's on top of her game. She has the first break point of this final set as Boulter wallops one into the net.
*Alcaraz 1-2 Rinderknech
Alcaraz is annoyed at himself as instinct sees him flick the racquet up at the net to send a volley wide, but he thinks Rinderknech's initial shot was going wide.
That would have put him 30-15 up but instead Rinderknech gets the hold.
Kessler 6-3 3-6 1-0 Boulter*
Oh that's much better. Wide serve + volley at the net takes Boulter to 30-30.
Kessler 6-3 3-6 1-0 Boulter*
Right, things are getting serious in Nottingham. Katie Boulter skids a backhand off her racquet wide to slip to 0-30.
Kessler 6-3 3-6 1-0 Boulter*
Decent start to the decider from McCartney Kessler, holding to love.
Alcaraz 1-1 Rinderknech*
It is a hold for Alcaraz but there was some good play in there by Rinderknech, who at one point races to the next to flick a volley just over. Alcaraz's serve gets the job done, however.
*Alcaraz 0-1 Rinderknech
An encouraging start by Rinderknech as he swiftly holds.
Alcaraz 0-0 Rinderknech*
We're under way with the third match on centre court today with Rinderknech serving first against the top seed.
Sophie Brown
BBC Sport
Just how will Carlos Alcaraz have recovered from last night’s gruelling win, which was the third longest match on record at Queen’s?
He probably won’t want to think about the last time he met today’s opponent Arthur Rinderknech because it was another marathon on the same court in 2023, with a shaky looking Alcaraz having a real battle in what was his first match at Queen’s. Like yesterday, the Spaniard had to come back from a break down in the final set to win on a tiebreak in 2hr 34mins. But thereafter he didn’t drop a set as he went on to win the title.
*Kessler 6-3 3-6 0-0 Boulter
Two-time defending champion Katie Boulter takes us to a decider. We get locked in another epic rally, which Boulter gets out of by producing a stunning lob.
Kessler only just returns it, but Boulter is able to easily finish things off with an overhead at the net.
The perfect set from the Briton. No break points faced while converting her one and only break-point chance.
Kessler 6-3 3-5 Boulter*
Important point, and a very long rally, but it's McCartney Kessler who blinks first, slamming a backhand into the net.
Kessler 6-3 3-5 Boulter*
Wide of the line! Boulter's forehand is just out.
Kessler 6-3 3-5 Boulter*
Return of the double faults. One set point is saved.
Kessler 6-3 3-5 Boulter*
Ace from Boulter, and what a time to get it. 40-15, two set points.
It will be interesting to see how much energy Carlos Alcaraz at the start of his match today because it was a long time in the sun for him yesterday.
The Spanish player needed three hours and 26 minutes to beat his inspired compatriot Jaume Munar 6-4 6-7 (7-9) 7-5.
That was the longest match at Queen's in 34 years and also extends Alcaraz's winning streak to 15 in a row on the tour.
He's up next on centre court this afternoon, taking on France's Arthur Rinderknech.
Kessler 6-3 3-5 Boulter*
Total top-edge from Katie Boulter and the ball loops, high, high into the air - and somehow bounces in.
But Kessler quickly refinds her bearings and buries a forehand into the corner to hold to 30, and make Boulter serve for the set.
*Kessler 6-3 2-5 Boulter
Top recovery from Boulter at 15-30 as McCartney Kessler smashes an overhead into the net, and then Boulter nabs the next point with a strong forehand down the line.
Kessler whacks the net again to hand Boulter a hold.
Jack Draper will play Jiri Lehecka in the semi-finals tomorrow.
Speaking on the court, he said: "The support I've received this week has been amazing. I am used to battling on the grass but to be in the semi-final here is something I've wanted since I was a kid, so it means everything to me.
"I think at times I've not played some great tennis and in those moments I've just tried to believe in myself and I think that is where the confidence has come from.
"Hopefully, I can carry onto the next round and get better.
"I keep on getting asked about top four seeding but I have to get to the semis first! To get to that position is an incredible feeling. It is testament to the work me and my team have done and I am proud of that."