‘Every time I’m on the pitch, I want to fight for this club.’ The words from Amad Diallo were on the front of Thursday night’s match programme alongside a photo of Manchester United’s new darling.

And thank goodness for United, Diallo did fight. Because for more than 80 minutes here at Old Trafford they were second best to bottom-of-the-table Southampton, a team that is still on course to become statistically the worst in Premier League history.

United trailed to a Manuel Ugarte own-goal. They were facing a fourth top-flight defeat in a row – equalling an unwanted record that has stood since 1930 – and a sixth in eight games under new head coach Ruben Amorim, who could only look on in agony.

Then Diallo decided to take matters into his own hands with a sensational 12-minute hat-trick. The little Ivorian who has emerged as a huge presence under Amorim with big goals against Manchester City and Liverpool this season to earn a new contract.

But this was something else altogether. With United in dire straits and Saints on the verge of a deserved win, he came to the rescue.

In the 82nd minute, Joshua Zirkzee found Diallo with a pass and he drove at Kyle Walker-Peters on the left. Diallo got a kind ricochet off the Saints defender and didn’t need a second invitation, seizing on the loose ball to bury it past Aaron Ramsdale.

The killer goal arrived in the 89th minute, latching onto a one-two with Christian Eriksen to poke home from close range and send Old Trafford into rapture.

Then in the fourth minute of added time, Diallo crowned an unbelievable performance as he stole the ball of Taylor Harwood-Bellis to score the third.

This was one of those nights when it was hard to say whether Southampton rose to the challenge or United were so bad that they made the worst team in the Premier League look good.

Thanks to Diallo they were able to build on their encouraging recent results and performances at the Emirates and Anfield.

It had lifted the mood here but also raised questions about the mentality of players who could go toe-to-toe with Arsenal and Liverpool yet lose four home games in a row to Nottingham Forest, Bournemouth and Newcastle.

Amorim was right to call them out and demand more of the same. If the United players were in any doubt about their head coach’s expectations, Amorim made it clear in his match programme notes. ‘In terms of fight, heart and hunger, we have seen the real Manchester United in the last two matches,’ he wrote.

‘In the past month we have been to the Etihad Stadium, Anfield and the Emirates – three of the toughest places to play in the country – and taken positive outcomes from each one. To do that requires quality and character, but the job now is to show that in every single game, regardless of the opposition.’

With six points and a goal difference of minus 32, Southampton arrived at Old Trafford with the worst record after 20 games in Premier League history. They had scored 12 goals, the fewest in the top five divisions of English football

But the mind drifted back to United’s 3-0 win at St Mary’s in mid-September when Andre Onana’s save from Cameron Archer at 0-0 turned the game in their favour when Saints were well on top. Small margins and all that.

Onana was back in goal, replacing Altay Bayindir following the Turk’s heroics in the penalty shoot-out win at Arsenal in the FA Cup. Diallo covered for the suspended Diogo Dalot after he was sent off at the Emirates, showing his versatility by playing at right wing back, and Leny Yoro took over from Harry Maguire who was only fit enough for a place on the bench.

The challenge for United wasn’t just in terms of their mentality, but their ability to prevail in games where they had far more of the ball. It is fair to say they came up well short in the first half.

After a bright start from the home side, it was Southampton who grew in confidence. Kamaldeen Sulemana gave Yoro a torrid time on the right, and he turned United’s £59million man in the 12th minute and forced a fine save from Onana before Mateus fired straight at the United keeper.

It was no surprise that United were better on the break and twice they sprang out with Bruno Fernandes the provider. First, he released Rasmus Hojlund and he squared for Alejandro Garnacho to sidefoot wide in front of goal. Then, Fernandes sent Kobbie Mainoo clear but he couldn’t find Garnacho with a simple pullback.

When Garnacho had shots blocked in quick succession by Jan Bednarek and Harwood-Bellis, it seemed only a matter of time before United would score.

But Saints when on the offensive again and Onana had to pull off a brilliant double save. Tyler Dibling had tormented United at St Mary’s and he did it again here, turning Lisandro Martinez and past three defenders to force another excellent stop from the Cameroonian who produced an even better one to keep out Fernandes’ follow-up with his chest from point-blank range.

But Onana couldn’t rescue United again when they conceded from another set-piece after Matthijs De Ligt scrambled the ball out for a corner three minutes before the break.