50' There's a half-chance for Mbappe now and PSG may wish they'd done more to help him put it away. The France international finds himself juggling a delivery under pressure inside the Brest box and defenders crowd him before he can either shoot or find an avenue to set up another effort.
48' The pressure will be on for the hosts here. Score early in this second half and they are in with a shout of forcing something from this game. The longer this goes on with no response on the scoreboard, the more their odds will lengthen.
46' We are back underway at Stade Francis-Le Ble. Is it plain sailing for PSG from here or can Brest spring a famous cup comeback?
If you are Mauricio Pochettino, do you remove Mbappe from the pitch at the break? The Argentine may have one eye on next week's Champions League second leg with Barcelona - and despite a hefty lead, he will be no fool in knowing the Blaugrana could mount an astonishing comeback. His most prized asset may need to be preserved.
A delightful top-drawer finish from Kylian Mbappe and a coolly taken half-chance for Pablo Sarabia means that PSG are firmly in front in the Coupe de France - but hosts Brest have more than played their pair. The visitors could well be home and dry, but they've been forced to fight for their lead. At half-time, it is Brest 0-2 Paris Saint-Germain.
45' HALF-TIME: BREST 0-2 PARIS SAINT-GERMAIN
42' This has suddenly turned into a far more robust test of the PSG defence than anticipated. Bakker sees off a long ball down the right flank again and the visitors have a goal-kick to help ease the pressure.
40' Now it is Danilo's turn to clear PSG's lines before Rico snaffles a return delivery. Brest are growing in confidence here, momentum swinging towards them as the game heads towards half-time.
38' Is that a Brest penalty? Diallo and Bakker sandwich Philippoteaux in the box and he goes down, perhaps a touch softly. The referee isn't having it and PSG are able to spirit the ball back to midway.
35' Mbappe hits the post! The striker can't believe it and nor can his team-mates. He's released through a gap in the Brest defence, cuts a lovely line and tries to pull his shot in at the far edge past Cibois, only to hit the woodwork. What an opportunity.
33' Philippoteaux is making himself known up front for Brest right now, but PSG are doing an excellent job at cutting off supply, having perhaps allowed the hosts more room to launch counter-attacks early on. It's getting a little bit nip-and-tuck around the ankles.
31' The visitors lash their latest free-kick into the box and Cibois helps usher it away. PSG continue to hound the keeper until he rids himself of the ball with a deep punt downfield though.
29' There's a little bit of frayed tempers with PSG and it is easy to see why; they've picked up that booking there despite a few hefty challenges against them going unpunished.
27' Oh, Sebastien Cibois may be the luckiest man on the pitch right now. He roars out of his box and puts a slide tackle straight into Mbappe's ankle, about six yards outside his area. He's not booked - doesn't even concede a free-kick! - because the PSG man had been offside. That's a stroke of fortune.
26' The visitors have had 62 per cent of possession so far, a fair reflection of their general composure and control in this game. They also seem very comfortable at ensuring Brest are harried when playing it out from the back.
24' You do wonder how nervous PSG might get the longer this game goes on without them adding a second. If they can double their lead before the break, they may be as good as home and dry. But at a one-goal lead, this is still risky territory in knockout football.
21' PSG will have a goal-kick now after a looping cross-turned-shot from Brest almost wrongfooted Rico at the back, sailing wide of the right post by a good few feet in the end.
19' Now it is PSG's turn to drive a few low deliveries into the Brest area of the pitch. The hosts cope admirable and Mbappe's attempt to twist a return cross in is picked off easily enough.
17' Again, Brest slip the delivery down into PSG's final third with a touch of invention and again, the visitors read it well. This is an intriguing tussle, but that one-goal lead still looks pretty secure as things stand.
15' It's a particularly still night in Brest, long balls catching the air with little wind. That could help the visitors if they decide they want to bypass the hosts' midfield entirely, which is not implausible.
13' Credit to the hosts, they've rallied admirable and ping a pair of dangerous balls into the PSG penalty area. Again, the end execution is missing, but they're not looking like a side woefully out of their depth against last year's Champions League finalists.
11' Chalk another one up for the France international; he may well be the most fearsome player at Euro 2020 later this year. That's a psychological blow for Brest so early here to recover from.
7' Sarabia with the chance! The striker will be kicking himself there, fed a lovely ball into the box that he can't turn and put away before Pierre-Gabriel robs him of possession. That was set up wonderfully.
4' That is some silky footwork from Brest! PSG's defence are furious with themselves and rightly so, cut open with some neat triangular play and a pair of delicious backheels that just don't quite come off at the end.
3' Early nerves for the hosts as PSG win a quickfire corner and Cibois fails to take it cleanly. He's fortunate the bounce is kind; the ball comes straight back into his gloves before it can be snaffled.
1' We are underway in this Coupe de France clash between Brest and Paris Saint-Germain!
The teams are out at Stade Francis-Le Ble and we are moments away from kick-off.
A Zlatan Ibrahimovic hat-trick ensured a 5-2 win for PSG the last time these two sides met in this competition, in January 2014. One player survives; Marquinhos, on the bench for the visitors as he was that day too.
Subs: Alexandre Letellier, Presnel Kimpembe, Marquinhos, Timothee Pembele, Layvin Kurzawa, Rafinha, Idrissa Gueye, Angel Di Maria, Mauro Icardi.
PARIS SAINT-GERMAIN (4-3-3): Sergio Rico; Thilo Kehrer, Danilo Pereira, Abdou Diallo, Mitchel Bakker; Ander Herrera, Marco Verratti, Leandro Paredes; Pablo Sarabia, Kylian Mbappe, Julian Draxler.
Subs: Brendan Chardonnet, Mouez Hassen, Julien Faussurier, Steve Mounie, Romain Perraud, Jean Lucas, Hugo Magnetti, Hianga'a M'Bock, Gaetan Charbonnier.
BREST (4-2-3-1): Sebastien Cibois; Ronael Pierre-Gabriel, Jean-Kevin Duverne, Lilian Brassier, Ludovic Baal; Haris Belkebla, Bandiougou Fadiga; Jeremy Le Douaron, Romain Faivre, Romain Philippoteaux; Irvin Cardona.
Those following the news may already know that Mauricio Pochettino has confirmed Neymar's absence for PSG today, but the Argentine isn't treating this like a kick-around tie too much either. A few faces are rested, but Kylian Mbappe's presence up front showcases the visitors' intent clearly.
In their way sits a side they've already downed once in 2021 - but as most people will tell you, all bets can be off in knockout football. That being said, Brest have not beat their visitors since 1985; it's been a long while since they trumped the capital club.
If there's one trophy to rival the top-flight for PSG's domestic monopoly, then it is this knockout competition. The visitors have won it every year since 2015, except for 2019 when beaten on penalties by Rennes in the final - and they're hot favourites to progress today once again.
Hello and welcome to live coverage of the 2020-21 Coupe de France, as reigning champions Paris Saint-Germain look to avoid a potential banana-skin result against fellow Ligue 1 side Brest at Stade Francis-Le Ble.