PARIS: Despite enjoying a near-perfect season on the pitch, Paris Saint-Germain is dealing with a major internal crisis on the eve of its biggest game so far.

The runaway French league leader should be full confidence as it prepares to welcome Chelsea at the Parc des Princes for the first leg of their Champions League last-16 match on Tuesday.

PSG is unbeaten in its last 44 domestic matches, and key players Javier Pastore and Marco Verratti have recovered from injuries in time.

Instead, a poisonous atmosphere enveloped the club over the weekend after defender Serge Aurier was suspended for insulting coach Laurent Blanc and some of his teammates in an online video.

During a live session with fans on social media, Aurier aimed abuse at Blanc and insulted Zlatan Ibrahimovic and Angel Di Maria.

Aurier has since apologized but could soon be placed on the transfer list.

The video left the club's Qatari owners unimpressed, and president Nasser Al-Khelaifi said he would not allow anyone to get away with damaging PSG's image.

Aurier's comments are a setback in Qatar Sports Investments' attempt to turn PSG into a world-class club. When QSI took over in June 2011, PSG endured serious problems of hooliganism and racism, and was everything but a model of sporting stability.

It has been transformed into one of the world's richest clubs, and the Parc des Princes has been cleaned of its most violent supporters. But PSG has yet to pass the quarterfinals of the Champions League, and the slick image its owners want to promote has been dented at the worst moment.

Aurier has been a key player for Blanc, and is widely regarded as one of the best right backs playing in Europe. But this isn't his first run-in with authorities, as he was suspended for three matches last year for insulting a Champions League referee on social media.

Against Chelsea, he is likely to be replaced either by Marquinhos or Gergory Van der Wiel. Ibrahimovic and Di Maria are expected to start up front, with Lucas Moura and Edinson Cavani in competition for a starting position on the left flank of the attack.

Here are other things to know about the match:

MAKESHIFT DEFENSE: The central-defensive pairing of Kurt Zouma and John Terry also has been integral to Chelsea's improvement under coach Guus Hiddink, but neither will be playing.

Zouma was ruled out for the season last week with a knee ligament injury, and Terry hurt his hamstring at the weekend, leaving Chelsea to likely throw together Gary Cahill and Branislav Ivanovic at center back to handle the threat of Ibrahimovic.

Cesar Azpilicueta will be moved to right back to accommodate Baba Rahman on the left.

COSTA REVIVAL: Striker Diego Costa is back to his best, and that spells danger for PSG.

He appeared to be more interested in fighting than scoring at the start of the season, but since Jose Mourinho departed, Costa has been more focused on his primary job, and scored eight goals in 10 games.

VERRATTI EXTENDS DEAL: Midfielder Marco Verratti has extended his contract with PSG until 2020. He has played a crucial role in PSG's rise to the summit of French football since his arrival in July 2012.

Blanc has often expressed his admiration for Verratti, who has 155 appearances.

PSG said the "contract extension demonstrates the importance of the 23-year-old midfielder."