Kylian Mbappe opened his account for the 2021-22 season as Paris Saint-Germain, still without Neymar or Lionel Messi, defeated resilient Brest 4-2.

With Messi and Neymar not judged ready for Friday's game by Mauricio Pochettino, Mbappe scored his first of the season with what was just his fourth headed goal in Ligue 1.

Mbappe put PSG 2-0 up, with Ander Herrera having opened the scoring, but Keylor Navas' error handed Brest a reprieve.

Idrissa Gueye's long-range strike seemed to have settled the contest, though it was ultimately substitute Angel Di Maria who had to wrap up the points after Steve Mounie had pulled another one back.

Mbappe's six attempts across the opening two Ligue 1 games failed to yield reward and the France star might have done better in the fourth minute, with his close-range shot saved well by Marco Bizot, though an expected goals (xG) figure of 0.065 suggested it was a difficult chance.

With Marco Verratti also going close, PSG's dominance told when Herrera tried his luck with a volley which crept in under Bizot, who did better to stop Achraf Hakimi doubling PSG's tally.

Little blame could be attached to Bizot soon after, however, with Mbappe charging in to get his head on a loose ball and divert a looping effort into the right-hand corner.

Navas had to hold his hands up at the other end before half-time, with PSG's shot-stopper failing to prevent Franck Honorat, the benefactor of Romain Faivre's exquisite flick, scoring despite getting a hand on the shot.

PSG's frustrations grew as they looked to add to their lead, yet Bizot's vulnerability from long shots came to the fore again as Gueye's dipping effort from 35-yards out evaded his grasp.

Navas atoned for his earlier mistake by denying Ronael Pierre-Gabriel, though Mounie did set up a grandstand finish with a cool 85th-minute finish.

There would be no fairytale comeback, however, with Di Maria – just nine minutes into his return – lobbing Bizot on the break to seal the points.

What does it mean? Defence a major concern for Pochettino

It is hard to imagine PSG not storming to the title this season, given the supreme quality at Pochettino’s disposal, yet first the former Tottenham boss simply has to get things sorted at the back.

PSG were, once more, all at sea defensively. Without Marquinhos, who has only just returned to the squad, Presnel Kimpembe delivered a performance hardly representative of his experience, while Thilo Kehrer looked out of his depth in the middle.

Five goals conceded in three games is a huge warning sign, and while Marquinhos and Sergio Ramos will no doubt help matters, Pochettino has to get the balance right.

Mbappe gets his head up

Mbappe thought he had opened his account for the season last week, only for his goal to be retrospectively put down as an own goal from Strasbourg's Ludovic Ajorque.

However, he got on the goal trail on Friday with what was his first headed goal for PSG since October 2019, and his first in Ligue 1 since March 2017, when he nodded in for Monaco.

Navas feeling the pressure?

Given Navas has been such an excellent signing for PSG, it was no surprise to see eyebrows raised when they moved to secure Gianluigi Donnarumma. However, the Italy goalkeeper was on the bench on Friday, and his hopes of immediately usurping the Costa Rican as first choice may have been boosted.

Though Honorat's chance for Brest's goal late in the first half was a good one (an xG of 0.353 means that, at that stage, it was the second-best opportunity in the game), Navas got down to what was a relatively weak shot, only to flap at it. With such an exceptional goalkeeper in reserve in the form of Donnarumma, the former Real Madrid man must do better to keep his place.

Fortunately for Navas, his blushes were somewhat spared by Bizot, who should have done far better for two of PSG's strikes. Indeed Gueye's winner had an xG of just 0.015 – the lowest of any attempt all game.

What's next?

PSG are away again – at Reims – before the international break, meaning Messi's debut may still well come on the road. It seems likely, with Mauro Icardi having gone off injured late on. Brest face Strasbourg in their next outing.