El Clasico is never an ordinary match.

But Sunday's meeting between Barcelona and Real Madrid carries more weight than usual.

With an 11-point lead over their rivals, Barcelona know that victory, or even a draw, at the Nou Camp would seal back-to-back La Liga titles and cap a dominant domestic campaign.

Real Madrid, by contrast, arrive under growing pressure after a week defined less by football and more by dressing-room unrest, player altercations and internal disciplinary action.

Against that backdrop, Real head coach Alvaro Arbeloa faces perhaps the biggest challenge of his short spell in charge: pulling together a fractured squad before one of the biggest matches in Spanish football.

Along the touchline, Hansi Flick has overseen a far calmer build-up, with Barcelona projecting confidence and control as they attempt to be crowned champions in front of their own supporters.

The first Clasico of the season in October went the way of Madrid, who earned a 2-1 win at the Bernabeu in a match played under very different circumstances, when the title race was far more open. Real had a different manager in Xabi Alonso and tensions were far less exposed.

This time, however, the stakes could not be clearer. Barcelona have the chance to lift the La Liga trophy at home after a match against their biggest rivals, while Madrid are fighting to delay the inevitable.

Questions surrounding the altercation between midfielders Federico Valverde and Aurelien Tchouameni dominated Arbeloa's news conference on Saturday.

The incident left Valverde ruled out of El Clasico because of concussion symptoms, while both players were fined 500,000 euros (£432,000) following a club investigation.

Tchouameni returned to training on Friday and remains available for the match, although Arbeloa declined to confirm whether the France international would start.

"The players have acknowledged their mistake, expressed their regret and asked for forgiveness. That's enough for me," Arbeloa told reporters.

"These two players deserve for us to turn the page and allow them to keep fighting for this club. I'm very proud of them. I won't allow this to be used to question their professionalism."

Former Liverpool, Real Madrid and Spain defender Arbeloa also suggested dressing-room disputes were not unusual in elite football environments.

"I've had a team-mate who picked up a golf club and swung it at another player," the 43-year-old said.

"What happens in the Real Madrid dressing room should stay in the Real Madrid dressing room, and that's what hurts me the most."

Arbeloa was referring to an incident during his time at Liverpool in 2007, when a disagreement between Craig Bellamy and John Arne Riise during a training camp in Portugal reportedly escalated into Bellamy confronting his team-mate with a golf club.

"These are situations that have always happened, although I'm certainly not justifying it," Arbeloa added.

"It was an incident and we were unfortunate that Fede ended up with a gash. It was more bad luck than anything else."

The Madrid coach also accepted responsibility for the situation.

"If you want to blame someone, here I am," he said.

Despite the controversy, Arbeloa insisted the focus remained on Sunday's meeting with Barcelona.

"We face the Clasico with the ambition to do things well and go to win."

Arbeloa does not appear to have a long-term future in his current post, with reports in Spain already linking several high-profile names, including Jose Mourinho, to the role for next season.

Pressure has also intensified on club president Florentino Perez, with questions being raised over a period that has seen Real Madrid go through three managers in two campaigns without lifting a trophy.

The club's next appointment is now viewed as one of the most significant decisions of Perez's presidency, as Madrid attempt to restore stability and competitiveness after a turbulent season on and off the pitch.

Despite the scrutiny, Arbeloa strongly defended the 79-year-old president.

"There is no-one more prepared than Florentino Perez to turn this situation around," he said.

"I remember how the club was before his arrival. He is the president with the most titles in Real Madrid history and he brought the club back to where it belongs. We all have to fight together."

Barcelona have projected a noticeably calmer atmosphere before Sunday's match.

The club shared a series of upbeat photos and videos from training throughout the week, with players appearing relaxed and united as they prepared for a fixture that could secure the La Liga title. One post was accompanied by the caption "One big family".

Head coach Hansi Flick said: "We want to win our second title in a row. I think it's amazing. It's not normal here in Spain.

"We are very clear in how we want to play. We want to win this at home. The fans are supporting us. This is why the Clasico is so important for everyone.

"We are here because we have played a fantastic season as a team and this is what I want to see tomorrow. The tension is very high. Everyone in the world is watching, but in the end it's about us. We want to play as a team and a unit."

Flick was asked about the incidents in Madrid and said: "Things like this happen all over the world, so I don't think it's something exclusive to Real Madrid.

"Was I surprised? Maybe a little, but in the end I don't really care, because it's not my club and not my team, so I shouldn't be thinking about it."

He instead pointed to the importance of unity within his own squad, saying: "The most important thing in this club is that we are all going in the same direction.

"When something happens, we respond together. In football and in life, these things can happen, but you have to manage them."

Asked about the debate over whether Real Madrid are better with or without Kylian Mbappe, Flick was unequivocal in his praise, describing the French striker as "one of the best players in the world" and highlighting his "unbelievable quality in the box and in front of goal".

For both sides, Sunday's Clasico carries enormous significance. Real Madrid are fighting for pride, while Barcelona stand on the brink of La Liga history.

Victory would keep Barcelona on course to match the league record of 100 points, moving them to 91 with three games remaining.

The landmark was first achieved by Mourinho's Real Madrid in 2011-12 before Tito Vilanova's Barcelona equalled it a year later. It is an achievement no side has managed since.

Reaching the century mark would be the ultimate reflection of Barcelona's dominance in La Liga during Flick's tenure. But before history can be made, one final Clasico must be won.