Alex Michelsen might be playing in his first Grand Slam quarter-final but he doesn't look like he's feeling much pressure.

The 22-year-old puts in another strong service game to hold to 15 and he's edging ever closer to the semi-finals.

Frances Tiafoe comes through a strong service game relatively untroubled.

The 11th seed can now have a breather at the change of ends, before trying to apply some pressure on Alex Michelsen's serve again.

The crowd are trying to lift Frances Tiafoe and they up the volume when the American 11th seed triumphs in a rally.

Tiafoe finds the pass next shot with Alex Michelsen at the net, but the world number 46 fights back brilliantly to secure the hold with some excellent defensive work at the back of the court.

Michelsen has proved tough to put away in the lengthy groundstroke exchanges today.

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Frances Tiafoe saves another break point before eventually coming through to hold, sealing the game with a backhand winner into the open court.

If Tiafoe lost that game you would have really struggled to see a way back for him.

Pam Shriver
Five-time Wimbledon doubles champion on BBC Radio 5 Live Sports Extra 2

We have to really give a lot of the credit to Michelsen, he's taken the serves and smothered Tiafoe.

Frances Tiafoe shrugs his shoulders as he puts a backhand into the net, before overcooking a forehand.

Tiafoe takes a deep breath at the back of the court before walking to the baseline to serve and despite getting the better of a rally, then offers break point to Michelsen as he goes into the net.

It would be a monumental mountain to climb if Tiafoe goes down two breaks here, but he wins the point to send the game to deuce.

Alex Michelsen serves his 11th ace of the match to get ahead, before Frances Tiafoe pulls a forehand wide.

Michelsen lets his American counterpart into the game with a double fault and Tiafoe takes advantage by forcing deuce with a strong forehand.

It doesn't come to anything, as Michelsen steps up with two strong first serves to secure the hold.

Pam Shriver
Five-time Wimbledon doubles champion on BBC Radio 5 Live Sports Extra 2

I'd be stunned if we didn't see some sign of nerves.

This for Michelsen, is the biggest set of his life!

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Frances Tiafoe needs a strong start to this third set but he finds himself under pressure early with two loose shots.

Alex Michelsen then does well to keep competitive in a rally, and brings up two break points as Tiafoe goes long with a forehand.

Tiafoe saves one with a lovely passing shot with Michelsen coming into the net, but can't rescue the second as he is beaten by backhand winner down the line.

Image source, Reuters

Pam Shriver
Five-time Wimbledon doubles champion on BBC Radio 5 Live Sports Extra 2

Tiafoe has twice in his career come from two sets to love down.

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Frances Tiafoe is handed a code violation for thumping the ball in frustration.

At the other end of the court, Alex Michelsen is cool as a cucumber as he brings up three set points.

The 22-year-old takes them at the third time of asking with a rasping forehand winner across court.

He's one set away from his first Grand Slam semi-final.

Alex Michelsen's mum is in the crowd on Arthur Ashe Stadium and she must be enjoying what she's watched so far from her 22-year-old son.

Frances Tiafoe has struggled for consistency today but he does enough to secure the hold as Michelsen puts a couple of forehands into the net.

Michelsen will now serve for a two-set lead.

Pam Shriver
Five-time Wimbledon doubles champion on BBC Radio 5 Live Sports Extra 2

"You've got to make your serves." That's the voice of [Tiafoe's coach] Mark Kovacs.

What a way to consolidate your break of serve as Alex Michelsen holds to love.

Frances Tiafoe must now serve to stay in the second set.

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Frances Tiafoe double-faults to put himself in a spot of bother before just coming up short in a monster rally which had the crowd on the edge of their seats.

Alex Michelsen played the finest of forehands at the end of that rally and it earned him a break point.

The world number 46 takes it as he comes into the net at just the right time to prevent Tiafoe being able to find the pass.

After being broken back in the last game, Michelsen responded brilliantly there.

Pam Shriver
Five-time Wimbledon doubles champion on BBC Radio 5 Live Sports Extra 2

Men come from two sets to love down all the time, but you get the sense that Frances Tiafoe has to win this set. The next 15-20 minutes is the most important part of the match for Tiafoe.

I want to see Tiafoe have a service game where his first serve looks free. He's playing handicapped at the moment because his first serve hasn't won him enough free points.

Can he find something in this quarter-final before it's too late?

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It's another break point for Frances Tiafoe but he just misses out with a forehand which drops the wrong side of the line.

Tiafoe gets another chance though, and the roars of encouragement from the crowd tell us they want him to take it.

I wonder if that gets into Alex Michelsen's head a little, as he then thumps a forehand into the net to gift Tiafoe the break a lot of the crowd wanted.

Pam Shriver
Five-time Wimbledon doubles champion on BBC Radio 5 Live Sports Extra 2

Tiafoe has lost some big matches here. Against Ben Shelton and lost an all-American semi-final to Taylor Fritz a few years ago.

I think the crowd will be right behind Tiafoe but he has to elevate his game and produce some of those charismatic points.

Frances Tiafoe is showing his frustration a little as he mistimes a forehand which loops wide.

He recovers well though as Alex Michelsen misses a couple of shots, before overcooking a volley at the net.

Tiafoe has break point but it's snuffed out with an ace.

Alex Michelsen sets the tone for the game with a smoking forehand winner down the line which Frances Tiafoe can do nothing about.

Tiafoe later goes wide to offer three break points, before closing both his eyes and looking to the sky in disappointment.

Tiafoe does well to save two, but can do nothing about the third as he is beaten by a backhand return winner down the line.

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