Nottingham Forest beat Tottenham 3-0 in the Premier League in December. Welcome to the disarray derby. The Premier League's chaos clubs meet on Sunday as Tottenham Hotspur host Nottingham Forest in what could be a seismic moment in the survival battle.

Forest - who gained momentum by reaching the Europa League quarter-finals on Thursday - are outside the bottom three on goal difference, Spurs just a point better off after another season of drama. The north Londoners could be relegated for the first time in almost 50 years with interim boss Igor Tudor failing to make an impact, despite Sunday's point at Liverpool, while Forest are on their fourth head coach of the season.

On Sunday, one club could go a long way to saving their season and edging the other towards the drop as crisis meets calamity.

'It's not Allan, it's Arne' - Tudor explains viral moment. Tottenham have rarely had such dark days, having finished 17th last season - albeit winning the Europa League under Ange Postecoglou. The Australian was sacked days later and replaced by Thomas Frank who lasted eight months before leaving in February.

Despite winning the second leg, Wednesday's Champions League exit against Atletico Madrid - following the calamitous first-leg defeat last week in which goalkeeper Antonin Kinsky was replaced after just 17 minutes - adds to the dysfunction. It was Tudor's first win - after three defeats and a draw - since he succeeded Frank, with his position having already been in doubt after just 34 days in charge.

Frank's arrival after Postecoglou's exit was meant to be the start of another rebuild following the Dane's impressive seven years at Brentford, but it only sowed more division amid player indiscipline, a split executive team and doubts over his tactical approach.

The Lewis family - which owns the Enic Group which holds a majority stake in Spurs - has come under fire, but group Change for Tottenham (CFT) has postponed a planned protest on Sunday, despite an "immediate generational threat" to Spurs' Premier League future, to focus on supporting the team.

"A lot of fans have truly given up," said CFT member Jay Coughlin. "It's been horrendous. Obviously there's been a call for all Spurs fans to be the 12th man against Forest. It's something where a lot of fans want to get behind the players and it's going to be seen as negative if there's anything towards the ownership."

It comes after a meeting with the club's fan advisory board this month when chief executive Vinai Venkatesham said he had overseen a comprehensive review. The results were a damning criticism of the club's failings.

Among the key issues identified were:

• Insufficient focus across the organisation regards on-pitch success
• A wage structure and player transaction approach that had impacted competitiveness in the transfer market
• The men's squad requiring strengthening in terms of quality, experience and leadership
• Financial pressures arising from heavy transfer spending and limited player sales, increasing the relevance of Financial Fair Play (FFP) constraints to future planning
• A growing disconnect between the club and its supporter base

Dan Lewindon has joined as performance director from the City Group and the club plan to appoint a director of football operations in the summer - but by then it could be too late.

Tottenham have not been out of the top flight since 1977-78 but are winless in the Premier League since December, with just two victories in their past 21 league games. It has eroded the already fragile trust from the fanbase towards the Enic Group, which holds an 86.58% majority stake in Tottenham, with former executive chairman Daniel Levy having a 29.88% stake in the company.

Coughlin told BBC Sport: "All of them deserve the blame and all of them have to face the music come the final game of the season when we know our fate. There has to be questions answered.

"I believe the two people, Vinai Venkatesham and [sporting director] Johan Lange, should not be keeping their jobs the way they've handled being in control of such a proud, historic club. It feels like this year they've sat there and laughed in our faces.

"The belief that we will be a Premier League club is, I'm hoping, still alive - but the reality is there is no club too big to go down."

Forest's plight has been self-inflicted but there is still more unity than in north London. Thursday's penalty shootout win at Midtjylland earned them a Europa League quarter-final tie with Porto, edging them closer to an early-season goal of winning the competition.

That was before four permanent managers this season - Nuno Espirito Santo, Postecoglou, Sean Dyche and now Vitor Pereira - which underlines the turbulent campaign at the City Ground. Nuno fell out with global sporting director Edu and owner Evangelos Marinakis, leading to his sacking, while replacement Postecoglou lasted just 39 days. Dyche never won over the players in his 144-day reign, leading Marinakis to recruit ex-Wolves boss Pereira in February, having worked with him at Olympiacos.

Despite the revolving door, Marinakis retains the support of the fans - in contrast to Spurs - with the club also having frozen season ticket prices.

"I'm sure the ownership - they're not stupid - will be looking at what the solutions are to the off-field problems," said James Bogue of the Nottingham Forest Supporters' Trust (NFST). "But nobody can argue it's not been self-inflicted. Nuno didn't get the new players that he wanted and it's all fallen out from there.

"The lessons will - and must - be learned, that you've got to get everything lined up on and off the field right."

Yet this campaign should have been the platform for Forest after last season's seventh place. They missed out on reaching the Champions League on the final day in May, then spent £180m in the summer to try to keep pace at the top. Few have made an impact, with £26m striker Arnaud Kalimuendo shipped to Frankfurt in January, and the loans of Douglas Luiz and Oleksandr Zinchenko cancelled. James McAtee and Dilane Bakwa, signed for a combined £60m, have made four league starts between them.

Forest could not have expected Chris Wood, who scored 20 goals last term, to miss the majority of the campaign with a knee injury, but despite the chaotic season Bogue believes fans would not change the ownership.

"Their ambition shines through," he said, with Forest having been promoted in 2022 after 23 years outside the top flight. "We love it. The ambition has taken us from the foot of the Championship to a team in Europe.

"Missteps have been made and it's a season which has fallen flat, but what do we want?

"Do we want owners who are not ambitious, who want to sit 13th and 14th, or do we want to strive higher? I'd go with the latter."