RANKED: Man Utd's best - and worst- seasons since Sir Alex Ferguson's retirement

The worst season of the post-Ferguson era began so well. With fans back at Old Trafford after almost 18 months away, Ole Gunnar Solskjaer's side thrashed old enemies Leeds United 5-1 with a Bruno Fernandes hat-trick.

A few weeks later, the club announced Cristiano Ronaldo's shock return, smashing social media records before the Portuguese enjoyed a dream second debut against Newcastle, scoring twice in a euphoric atmosphere.

Ronaldo inspired thrilling comebacks against Villarreal, West Ham and Atalanta, but the wheels started to come off in October, when United were hammered 4-2 by Leicester City and then 5-0 at home to Liverpool.

The 2-0 defeat by Manchester City was arguably more demoralising, and Solskjaer's death knell was signed by a 4-1 thrashing at Watford.

Michael Carrick avoided defeat in his three-game caretaker spell in charge before Ralf Rangnick was hired as interim manager.

Much optimism about the German's tactical influence on the modern game soon gave way to more doom and gloom as United won just three of their final 14 matches.

They exited the Champions League and FA Cup limply, suffered more humiliating defeats to Liverpool, Man City, Brighton, Everton and Crystal Palace, and ended the season with their lowest-ever points total in 30 Premier League seasons.

"Your job is to stand by the new manager," Ferguson told United fans in his last appearance at Old Trafford, looking out at a banner of David Moyes reading 'The Chosen One'.

Supporters could have no idea at the time just how much they would need to stand by the new man, who lost three of his first six Premier League games.

Moyes soon found that a decade overachieving at Everton was scant preparation for the demands of United, and serial winners such as Rio Ferdinand and Robin van Persie did not appreciate his coaching methods.

The fear factor United had enjoyed under Ferguson vanished in a flash, and the likes of West Brom, Newcastle and Everton enjoyed their first ever wins at Old Trafford in the Premier League era.

A club-record signing in Juan Mata and the unearthing of Adnan Januzaj could not stop the rot and Moyes, who had been handed a six-year contract in 2013, was sacked after only nine months in charge following a limp defeat at his former home, Goodison Park.

Ryan Giggs stepped in as caretaker manager for the remainder of the campaign as United finished seventh, missing out on European football for the first and only time since 1989.

Insiders could tell that something rotten was in the air at United in the summer of 2018 and that discontent was brewing.

Jose Mourinho had failed to land a new centre-back and had fallen out with record signing Paul Pogba again.

United then lost two of their first three games, with Mourinho lashing out at journalists after the 3-0 defeat at home to Tottenham with his infamous 'respect, respect, respect' tirade.

His departure seemed inevitable, and was sealed after a disheartening defeat at Liverpool.

No one expected much from Solskjaer as a caretaker manager, but United went on an incredible run of 10 wins out of 11 under the much-loved former striker, and the 'Ole's at the wheel' chant was born.

The highlight was the stunning Champions League comeback in Paris, which led to Solskjaer's interim role becoming permanent.

But that was also when the honeymoon ended. Of their 12 matches after knocking out PSG, United lost eight while winning just two, suffering quarter-final defeats to Wolves and Barcelona in the cups and finishing sixth in the table, missing out on Champions League qualification.

There was plenty of promise heading into Louis van Gaal's second campaign after a strong finish to his first, and United spent big on exciting summer arrivals such as Memphis Depay, Morgan Schneiderlin, Bastian Schweinsteiger and Anthony Martial.

David de Gea even ended up staying after a botched deadline-day move to Real Madrid.

There was huge excitement when Martial scored on his debut against Liverpool in an impressive start to the season, but a reality check came in the form of a crushing 3-0 defeat by Arsenal.

A series of drab results followed, including goalless draws against Crystal Palace and West Ham, before a shocking run of three consecutive losses to minnows Bournemouth, Norwich City and Stoke City.

United were also eliminated from the Champions League after being handed what looked to be a simple group containing Wolfsburg, CSKA Moscow and PSV.

Overall, there was a feeling that Van Gaal's possession-based football was out of date and excruciatingly dull, and the team ultimately failed to qualify for the Champions League after throwing away the lead to lose at West Ham in the final match at Upton Park.

There were some green shoots, such as Marcus Rashford's stunning emergence from the academy with braces against Midtjylland and Arsenal, plus away wins at Liverpool and Man City.

And there was the FA Cup run, the trophy sealed by Jesse Lingard's brilliant extra-time volley to beat Palace.

But even that moment of joy was quickly extinguished by the news that Van Gaal was about to be sacked to make way for Mourinho.

Solskjaer's first full season as manager was full of highs and lows.

It began with an emphatic 4-0 win over Chelsea, but was swiftly followed by draws with Southampton and Wolves, plus defeats to Crystal Palace, West Ham, Newcastle and Bournemouth by early November.

Then there was the unlikely win away at City, but another reality check came with a dismal defeat at Watford and demoralising losses to Arsenal, Liverpool and Burnley.

The signing of Bruno Fernandes lifted the mood and the Portuguese spearheaded a remarkable revival.

United won nine of their last 14 games while remaining unbeaten and ended a long campaign, which had been broken up by the coronavirus pandemic, sat in third.

After the traumatic season under Moyes, there was a huge feeling of optimism around Old Trafford with the arrival of Van Gaal, who had won titles in Spain, the Netherlands and Germany, and had just taken his national side to the World Cup semi-finals.

United had an excellent pre-season before Champions League winner Angel di Maria arrived, with Radamel Falcao soon following him.

All that hope was quickly dashed with a shock home defeat to Swansea City on the opening day, and United took just two points from their first three games before being thrashed 5-3 by Leicester.

The team soon began to adapt to Van Gaal's style of play, though, and won six consecutive league games during an unbeaten run stretching 10 matches between November and January.

Another impressive winning streak came between February and April, with Juan Mata starring in wins over Liverpool and City, as the team raced towards a top-four finish.

But there was still a sour end, with United picking up only five points in their final six league games.

At face value, this season could be ranked as United's best of the post-Ferguson era.

For only the second time since the Scot left, the team finished second in the Premier League and were in the title race until February. Remarkably, they ended the season unbeaten in the league away from home.

They enjoyed their biggest league win in 26 years by hammering Southampton 9-0 and reached the final of the Europa League, thrashing Roma 6-2 and Real Sociedad 4-0 along the way.

But the fact the whole season played out in empty stadiums meant no-one could say they truly enjoyed the journey.

And there were some inexplicable defeats, such as losing 6-1 to Tottenham and falling 2-1 at home to a terrible Sheffield United side which sucked momentum out of the title bid.

There was also more disappointment in the Champions League, losing at Istanbul Basaksehir with some diabolical defending and being knocked out of the group stage by RB Leipzig, having hammered the Germans just weeks earlier.

Worst of all was the club's involvement in the failed European Super League launch, sparking furious protests which led to the match with Liverpool being called off after fans invaded Old Trafford.

United may have had a bad league season in 2016-17, finishing sixth, but the power of winning trophies cannot be underestimated, and United won two.

Mourinho's arrival as coach did not go down well with all supporters due to his pragmatic style of play and his tendency to cause division, but his winning mentality appealed to others.

The world-record signing of Paul Pogba also rallied the fanbase, while Zlatan Ibrahimovic was an instant hit with supporters, scoring three times in his first two matches.

After a crushing 4-0 defeat by eventual champions Chelsea, United went on a 25-match unbeaten run and soon almost every fan was on Mourinho's side.

Winning the League Cup with a late strike from Ibrahimovic helped the Portuguese's cause, before the highlight of the season came with a comprehensive 2-0 win over Ajax in the Europa League final, securing Champions League qualification for the following campaign.

Erik ten Hag feels like Manchester United's best manager since Ferguson. He has restored discipline and values to the team, while the episodes with Ronaldo and Rashford showed everyone who is boss.

The Dutchman takes every game seriously and wants to win it all. He has got the players feeling the same way. Just witness how serial Champions League winners Raphael Varane and Casemiro, and World Cup winner Lisandro Martinez celebrated the Carabao Cup triumph.

Ten Hag knows football is about glory, and after so many disappointing seasons in the cups, United fans savoured beating Newcastle at Wembley and are relishing the FA Cup final against Manchester City after overcoming Brighton on penalties.

There have been numerous other highlights, such as beating Arsenal, Liverpool, City and Barcelona at Old Trafford, which is a fortress once more. United have won 23 out of 29 home games in 2022-23.

They are also set to return to the Champions League. After the horrors of the previous campaign, any United fan would have been pleased with finishing in the top four, winning the Carabao Cup and making the FA Cup final.

However, this season has also had its own harrowing moments, such as the 4-0 defeat at Brentford, the 6-3 thrashing at Man City and the historic 7-0 humiliation at Anfield. Even in the last month, United have been outplayed at Newcastle and battered by Sevilla.

Those results show how far United still have to go to return to the heights scaled under Ferguson.

But if they can seal the top-four finish and beat City in the FA Cup final, then it will be regarded as the best campaign of the post-Ferguson era.

United's second season under Mourinho yielded their best performance in the Premier League of the last decade. They ended the campaign with 81 points, their best total since Ferguson, and it would have been good enough to win the league in both 2015-16 or 2010-11.

They also reached the FA Cup final, only losing 1-0 to Chelsea thanks to an Eden Hazard penalty.

In the league, United beat Liverpool and Chelsea, and did the double over Arsenal. The problem was that their achievements were blown out of the water by a relentless Manchester City, who romped to the title with 100 points.

One saving grace for United was spoiling City's title coronation by coming from two goals down to beat Pep Guardiola's side 3-2.

It was also a disappointing season in Europe, being knocked out of the Champions League in the last 16 by Sevilla, with Mourinho making it all about himself again afterwards and ranting about "football heritage" in a bizarre press conference.

What happened next showed that even when Mourinho was at his best, disaster was never far away.