Beautiful from Jakub Mensik - one of his best shots of this set, a backhand winner down the line.

Ace down the middle.

Joao Fonseca finds an ace at a key time to make it 30-30 and move two points away from the set.

But then a double fault! Break point!

Comfortable enough for Jakub Mensik.

Over to you, Joao Fonseca.

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The noise level is going up inside Court Philippe Chatrier now as Joao Fonseca moves into a 5-3 lead under the roof.

Jakub Mensik is now serving to stay in the set.

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There's the break!

Joao Fonseca turns up the dial when required to restore that break of serve.

Early days, but we're not going the distance again, are we?

Jakub Mensik's first-serve percentage has dropped considerably in the third set.

Joao Fonseca finds the line with a forehand and now he has three more break points.

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There's not quite the same snap in the groundstrokes from both players and more errors are creeping in, which is perhaps to be expected as neither has made it this far in a Grand Slam before and they've both gone through the mill physically to reach the quarter-finals.

Joao Fonseca wraps up a service hold with an ace for 3-3 in the third set.

Whoops - a slam dunk smash attempt by Jakub Mensik lands well out. Pete Sampras was the master of that type of shot and I've rarely seen anyone do it better.

Mensik stretches out his leg or maybe his hip as he walks back to his serving mark.

Joao Fonseca can't take advantage and Mensik leads for the first time in the third set.

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Joao Fonseca dumps a drop shot into the net and Jakub Mensik gets the break back.

Jakub Mensik puts away the smash at the net.

A fourth break point for the Czech.

Naomi Broady
Former British player on BBC Radio 5 Live

This has been a sloppy game really.

Big.

Wonderful drop-shot winner from Joao Fonseca gets him to deuce.

A wild forehand wide by Joao Fonseca and now he's facing three break-back points.

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A chance for Jakub Mensik to regroup at the changeover, having held serve from deuce to get on the scoreboard in the third set.

After an excellent first couple of sets, something just doesn't seem quite right in the third so far.

Much better from Joao Fonseca, who finds a winner with that wicked forehand right at the start of his service game.

Jakub Mensik throws in a couple of unforced errors and that's an easy hold.

Wow - Jakub Mensik, on second serve, stuck it all on red and the ball on the roulette wheel landed in black.

A third double fault of the game and Joao Fonseca breaks right at the start of the third set.

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A massive scream of "allez!" from Joao Fonseca as Jakub Mensik again goes long.

A massive serve out wide which Joao Fonseca can't get back.

Deuce.

OK, so a couple of double faults bring up deuce and then Jakub Mensik goes long with an attempted lob.

A first break point of the match for Joao Fonseca.