Former England captain David Beckham is set for his debut for Paris Saint-Germain this weekend in a showdown with fellow Englishman Joey Barton's Marseille at the Parc des Princes.

This latest edition of what has come to be known as 'Le Classique' is one of the most important in years, with PSG coming into the weekend three points clear of Lyon at the top of Ligue 1, and five points above Marseille in third.

The outcome of Sunday's encounter could go a long way to deciding who is crowned champions at the end of the season, but the possibility of seeing David Beckham finally make his PSG debut in the game adds an even greater element of intrigue.

If he does play, there is the prospect of seeing the 37-year-old Beckham go directly up against his fellow countryman, Marseille's Joey Barton.

They are two men who represent the polar opposites of English footballing culture.

Renowned 'bad-boy' Barton has raised doubts as to how much of an impact Beckham can make at PSG, and expressed confidence that the visitors can still have a major say in the title race.

"He is a super ambassador for English football, but he is maybe not the athlete he was five years ago because, without wanting to disrespect the MLS (where Beckham last played for the Los Angeles Galaxy), it is not the same level," Barton told sports daily L'Equipe.

"We are just behind them in the table, and we are getting to the end of February. It is now that championships are won and lost," he added.

"We are the outsiders, but that status suits us."

As league leaders, and the financial powerhouse of French football, PSG come into this game as favourites.

However, there is extra pressure on them to get a result after their shock 3-2 defeat away at struggling Sochaux last weekend.

While Beckham has trained normally with his new teammates this week, question marks surround the fitness of Lucas Moura and Jeremy Menez, but Javier Pastore seems certain to start the game.

"The level of motivation is always huge for this type of match," said the Argentine, whose first impressions of Beckham have been good.

"He is a great player and a great person. I thought he would be a little bit detached from the rest of us, but he is very humble."

"To be able to share these moments with him in the changing room and on the pitch is a very positive thing."

Elie Baup's Marseille side have not been convincing since the winter break, and needed an injury-time strike from Rod Fanni to beat Valenciennes 1-0 last weekend.

The problems are building up for them too, with Jordan Ayew ruled out due to suspension and Morgan Amalfitano and Benoit Cheyrou both injured.

Lyon bounced back from successive league defeats to crush Bordeaux 4-0 away last weekend, but they face a tough test at home to Lorient less than 72 hours after their last-gasp elimination from the Europa League at the hands of Tottenham.

Lorient could pose a serious threat to Remi Garde's side, especially as they have had a full week to prepare for the game.

Jean-Michel Aulas, the outspoken Lyon president, this week complained that his team are being treated unfairly in being made to play on Thursday evening and then again on Sunday afternoon.

"There is a desire to make things difficult for Lyon against Lorient, who have not played during the week," he insisted.