• Newcastle romp to victory at St James' Park to boost Champions League hopes
  • In absence of manager Eddie Howe, Magpies run out 4-1 winners over poor Man Utd
  • Ruben Amorim's afternoon disintegrates after half-time interval

Manchester United's season went from bad to worse as they capitulated to a heavy 4-1 defeat at Champions League-chasing Newcastle United.

Ruben Amorim has endured a number of miserable afternoons and evenings since his appointment as head coach last November and his trip to the North East will have left him with another stress-induced headache.

Newcastle were by far the better team, particularly in the second half, and looked a cut above a United team who must now lick their wounds before Thursday's Europa League quarter-final second leg tie with Lyon – a game their season now depends on as they sit an abysmal 14th in the Premier League table.

How the game unfolded

Newcastle were unchanged from their cruise control 3-0 win over Leicester City on Monday, starting Jacob Murphy, Alexander Isak and Harvey Barnes in a front three as Anthony Gordon returned to the bench after injury.

Amorim made a number of changes to his team, including in goal, as he sought to balance the workload of his squad ahead of focusing on the Europa League – United's only route into Europe next season is to win that competition.

The Magpies, in a sign of what was to come, had the ball in the back of United's net in less than 45 seconds, but Joelinton's finish from inside the six-yard box was chalked off as Kieran Trippier had strayed offside in the build-up.

Murphy then fired wide as Newcastle made a fast start in the absence of unwell manager Howe, before Nick Pope had to be alert at the other end to deny Joshua Zirkzee after a superb interchange of passes involving Christian Eriksen and Bruno Fernandes.

The deadlock was broken midway through the half as Isak proved he's more than just a finisher, controlling Trippier's fired low pass to loft over the top for the onrushing Tonali who superbly fired home on the volley.

Altay Bayindir, starting his first Premier League game in place of the dropped Andre Onana, then made a super double stop to deny Tino Livramento and Isak – saves that turned out to be crucial as United levelled proceeding four minutes later.

Alejandro Garnacho was the goalscorer for the Red Devils, capping a fine breakaway down the right flank instigated by Diogo Dalot, who continues to blow hot and cold. The Argentine's first-time finish lacked power but was precise and placed just out of the grasp of Pope – it was just his second goal in his last 29 games for the club across all competitions.

Such has been United's season, though, the good news didn't last long. Still digesting their half-time cup of tea and bourbon biscuits, Amorim's side were caught cold by more fantastic play from Livramento down the left – the young Englishman's footwork leaving the aforementioned Dalot looking like a rabbit in the headlights.

His low cross to the back post was turned back into the six-yard box by Murphy, allowing the arriving Barnes to slide past Bayindir from close range.

United then lost Zirkzee to injury and used the break in play to make a triple substitution, which saw Mason Mount continue his comeback, but the momentum was with the home side.

Roared on by their usual vociferous support, Newcastle extended their advantage as Noussair Mazraoui's slip was punished by the electrifying Barnes. The former Leicester winger gave Bayindir no chance with his finish – rifling home with power after bursting into the penalty area. Soon after, it was four – a horrendous mistake from Bayindir punished by the ice cool Guimaraes.

Newcastle could, and perhaps should, have added more, while United, who were on the wrong end of a Toon league double for the first time in 93 years, were toothless in attack despite the best efforts of Bruno Fernandes.

All the talk pre-game surrounded Ruben Amorim's rumoured decision to drop goalkeeper Andre Onana – rumours that proved to be accurate when the teamsheets were confirmed.

Onana has endured a miserable time of late and engaged in a bizarre off-field spat with former United midfielder Nemanja Matic last week before dropping a stinker of a performance against Lyon in the first leg of the pair's Europa League quarter-final tie. The Cameroonian was at fault for both goals, with his 95th minute handling error, that allowed Rayan Cherki to level the game, a particularly glaring faux pas.

His general handling has been circumspect all season long while off the field, Onana's wife was the victim of a violent street robbery in late March, with thieves snatching a designer bag and Rolex watch as she went to meet a friend.

Amorim's decision to make a change was likely the right one, all things considered, and the Portuguese coach was arguably put in a no-win situation – leaving Onana in the side could do further damage while giving him a moment to catch his breath will no doubt attract criticism as well.

Bayindir, who shone for United in their penalty shootout win over Arsenal in the FA Cup third round in January, did little to stake his claim for a regular gig. In fact, he made an awful mistake as glaring as anything Onana has done this season, dinking the ball straight at Joelinton in the lead-up to Newcastle's fourth.

The adulation of the St James' Park faithful is shared around pretty evenly, but those watching from the outside in often flock to Bruno Guimaraes when it's time to throw around praise.

The Brazilian is a wonderful player – you don't have Manchester City, Real Madrid and Barcelona chasing you unless you are – and he is the one who ticks things over in the heart of Newcastle's midfield. But equally as impressive are regular partners Joelinton and Sandro Tonali, the latter of whom showed his box-to-box capabilities in some style.

The Italian came to the North East with a reputation for being a tenacious, tough-tacking defensive midfielder who was also very capable on the ball. But he's flourished into a far more rounded footballer under Eddie Howe, building on his existing skillset to make lung-bursting runs into the area when the situation dictates.

Such a situation arose here, and boy did Tonali take his chance well.