Recently you gave the symbolic kick-off for Lens-Troyes. What did this return to the Stade Bollaert-Delelis mean to you?
It has always been a pleasure to play at Lens, even though I didn't win there often. The atmosphere at Bollaert is exceptional. In France, I was lucky enough to play at OM and Strasbourg, two clubs known for their great atmosphere. At Bollaert, it's the same level. There is a whole nation behind the team. Win or lose, we were always happy to go to Lens, for the atmosphere and because after the match, we went to eat chips with our friends! I have many good memories here. I scored at Bollaert during a promotion play-off with Strasbourg and it's always impressive to silence 40,000 people. Unfortunately, it didn't last long because they ended up winning (3-1 in May 1991) and it was Lens who got promoted. I also scored with OM in my last game there - I took a penalty after coming back from injury (1-0 in April 2003).

Like OM did when you were there, almost half of clubs in Ligue 1 Uber Eats now play with a three-man defence. Is it a system that you like?
I really like it! My real position on the pitch was libero, a position that doesn't really exist anymore. With three central defenders, we find a bit of that libero because the three defenders 'pass' the opposing forwards. This system allows you to strengthen your midfield, the sector of the game where you win matches, in my opinion. It is a system that is as promising offensively as it is defensively. The pitch is perfectly divided. Having players on the flanks can be useful but what is needed is to have people in the middle, be it to recover possession or to score more easily.

In recent weeks, PSG have sometimes used a three-man defence. Has it been convincing?
What is certain is that I have my opinion on the subject! I think Paris are waiting for Sergio Ramos to come back so they can line him up in a three-man defence with Marquinhos and Kimpembe. I think it's compulsory for PSG to play with three at the back to compensate for the lack of defence from the front three. They need more players in midfield, with Gueye and Verratti in central roles, or Pereira when Verratti is not there. They need to be strong in this area to allow Hakimi, Bernat and Mendes to play much higher up - which would also be helped by better coverage at the back. At the moment, PSG are often drowned out in the middle and the two central defenders get beaten when there is an opposing attack. It's very complicated and there is lots of finger-pointing, but I think that PSG's squad is such that it can't work without a three-man defence.

Presnel Kimpembe has had a few complicated matches recently. What advice would you give him?
You have to trust yourself. The qualities that allowed him to get to this level are still there. There have been some really bad mistakes, but the penalty against Leipzig was just an error of inexperience. He's lucky to have Marquinhos next to him, and he should watch and learn. I've been lucky enough to play with great centre-backs - Marcel Desailly in particular. It's important to observe how these players work. Presnel Kimpembe reminds me a bit of Carlos Mozer. He was an extraordinary defender but he made almost one mistake per game with OM. A big tackle, a big foul, a bad touch... But he was still an exceptional player. Presnel has to trust himself. Carlos Mozer remained unperturbed, and Presnel must do the same.

Speaking now of your former clubs, what is your view of OM's season?
It's not bad at all, OM are playing attacking football! At the beginning, I was rather resistant to the Sampaoli method, especially in relation to what we had seen with the Argentinean national team. I was afraid that it would be a mess but I think the team is doing well, they plays good football, they're balanced... And Dimitri Payet is quite phenomenal at the moment. The whole team is very promising, they're not far off being the second-best team in France. But they need a few more very good players to really fight for the title.

And what do you think of Strasbourg's start to the season?
Racing are fighting with the means at their disposal. It's not a club with a lot of money but Marc Keller and the Strasbourg board are doing everything to make it work. I was a bit scared at the beginning of the season but things are stabilising. The match at the Parc des Princes was promising. They recently won 4-0 against Lorient at home. Compared to last season, they have their 12th man back and the atmosphere at the Meinau is quite extraordinary. Strasbourg have a team with heart. All the players who sign there know that they will have to work hard. Racing are not doing too badly this season, I am quite proud of them!