Manchester United sealed qualification for next season's Champions League with a 4-1 thrashing of beleaguered Chelsea on Thursday.
Casemiro, Anthony Martial, Bruno Fernandes and Marcus Rashford were on target as the Red Devils moved up to third in the Premier League.
A miserable night summed up Chelsea's season despite spending over £500 million in the transfer market as they slumped to an eighth defeat in 10 games since Frank Lampard returned as interim manager.
By contrast, confirmation of a top-four finish rounds off a successful first season in charge for Erik ten Hag after also ending United's six-year trophy drought by winning the League Cup in February.
More silverware could be to come next month should United halt Manchester City's charge towards the treble in the FA Cup final.
But a return to Europe's elite competition next season was one of Ten Hag's primary aims when he took the reigns after a disastrous 2021/22 campaign when United finished sixth.
Casemiro's arrival from Real Madrid has been fundamental to United's revival.
The 31-year-old's class and experience shone through against a youthful Chelsea side that were punished for a lack of efficiency in both boxes.
Mykhailo Mudryk should have netted his first Chelsea goal when the Ukrainian sliced wide a glorious chance on five minutes.
Just 60 seconds later, the visitors trailed as Casemiro was afforded a free header to turn home Christian Eriksen's free-kick.
Chances continued to flow at both ends as a poor first touch from Fernandes and Martial cost them with just Kepa Arrizabalaga to beat.
At the other end Kai Havertz headed wide and Conor Gallagher flashed a shot across David De Gea's goal.
United winger Antony was then forced off on a stretcher with an ankle injury that will make him a major doubt for the FA Cup final in 10 days' time.
But the home side ended the game as a contest in first-half stoppage time when Casemiro's no-look pass opened up the Chelsea defence for Jadon Sancho to square for Martial.
Ten Hag's men should have had more goals to round off a fine night in the second period as Fernandes smashed against the bar and Eriksen somehow failed to turn in Tyrell Malacia's cross from point-blank range.
Fernandes did finally get his goal from the penalty spot after the Portuguese midfielder was brought down by Wesley Fofana.
More calamitous Chelsea defending invited Rashford to become the first United player in a decade to score 30 goals in a season.
Fernandes pounced on Fofana's loose pass and teed up the England international, who needed two attempts to beat Kepa Arrizabalaga.
The waste of Chelsea's season can be summed up by the £10 million loan fee splurged on Joao Felix in January for a few months with little left to play for.
But the Portuguese international showed a glimmer of his quality with a surging run and low finish for a late consolation that denied De Gea his 18th clean sheet of the season.
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