Nothing sums up a difficult England camp quite like a teenager who was initially overlooked ending up making a near irrefutable case to go to Euro 2024. Kobbie Mainoo was originally fast-tracked into the Under-21s setup before manager Gareth Southgate drafted the Manchester United midfielder into the seniors amid concerns over a lack of cover in the middle of the pitch.

Jude Bellingham may have scored the stoppage-time goal which salvaged a 2-2 draw against Belgium on Tuesday, but it was Mainoo who stole the show with the sort of performance that dramatically accelerated his improbable late run towards Southgate’s final 23-man squad for the summer. Former England captain Gary Lineker suggested Mainoo had “not only played himself into the squad for the Euros but quite possibly the starting line-up” after a display in which he had a key role in England’s opening goal, completed 42 of his 47 passes and left as a 74th-minute substitute to a warm ovation involving a long embrace from Southgate.

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“He seems very mature, very calm, he knows he is making his way,” said Southgate. “We are absolutely delighted with what he’s done, first and foremost. But then there’s a lot of the season still to be played with his club so it is pointless me… I had a plan on Saturday night for Tuesday that got blown apart in 12 hours so to plan for [the Euros squad] in two-and-a-half months’ time is frankly ridiculous.

“So we know some of the core parts of that, we know who has been able to play at that level, who are very best players are. And the rest, we’ve got a lot clearer picture of what people are capable of from the two games we have played [against Belgium and Brazil] and we are just going to see how people are when they come back into form, whether they can do that fitness-wise with their clubs.”

Southgate’s original aim during this camp was to advance England’s aim of becoming a possession-based side capable of dictating big games but instead faced complications at almost every turn. Injuries to several players including captain Harry Kane were compounded by the revelation that Ben White rejected a call-up, before a row involving the St George’s Cross on England’s new Nike kit created a draining sideshow to on-field pursuits.

Further withdrawals arising from fitness issues — Kyle Walker, Harry Maguire and Sam Johnstone returned to their clubs on Sunday — only enhanced the patchwork feel to Tuesday’s line-up. Yet somewhere in the midst of all this, Mainoo was added to the group and immediately impressed in training, taking his latest elevation with the same composure that has accompanied his rapid rise.

Mainoo made his Premier League debut for United just 121 days ago. In January, he scored his first professional goal, netting a dramatic winner in stoppage-time as United beat Wolves 4-3 at Molineux. A promising 15-minute cameo in Saturday’s 1-0 defeat to Brazil preceded a full debut here at 18 years and 342 days, becoming the third-youngest United player to start a game for England behind Duncan Edwards and Marcus Rashford. And it was his progressive passing which triggered the move that helped England cancel out Youri Tielemans’ 11th-minute opener.

Mainoo’s quick feet and speed of thought enabled him to feed Bellingham who in turn played in Ivan Toney who was too quick for Jan Vertonghen and got a toe to the ball first before being fouled in the box. Toney, earning his second cap exactly one year after his first, converted the penalty with customary aplomb, becoming the first Brentford player ever to score for England in the process.

England’s defensive errors continued to undermine their performance. Jordan Pickford gifted possession cheaply for Belgium’s first goal before Lewis Dunk failed to clear his lines under pressure from Romelu Lukaku, who produced a sublime cross for Tielemans to head Belgium back in front on 36 minutes.

Declan Rice, captain for the evening on his 50th cap, engaged in lengthy dialogue with Mainoo as the players waited to kick off the second half and the Arsenal midfielder had his back all evening, enabling the 18-year-old to drift forward trying to affect play in the final third.

The nutmeg on Amadou Onana will make Mainoo’s YouTube compilation videos, so will the sharp spin away from Tielemans. More fine play on the edge of the box from Mainoo led to Joe Gomez — on for John Stones as the injuries continued to pile up — crossing to Bellingham, who inexplicably planted a header wide. His first-half miss when Mainoo pressed Onana high up the pitch was even worse. Bellingham eventually saved the day with a cool low finish in stoppage-time after good work from substitute James Maddison, but it was Mainoo who left the most pronounced impression.

England have lacked the sort of composed deep-lying midfielder Mainoo is developing into for years. Southgate has frequently discussed his lack of options at number six, but Mainoo looks to be capable of offering genuine guile as a number eight, refreshingly different to the more physical attributes of Conor Gallagher or Jordan Henderson.

It would be a huge ask of Mainoo — with just 20 senior appearances at United to his name — to anchor England’s midfield at the Euros, but he has emerged as an intriguing alternative and an unexpected positive from a camp that has required more improvisation than the meticulous Southgate would like given they now do not play again until he picks his Euros squad, likely to initially comprise an expanded long list.

“The injuries are a concern,” said Southgate. “We’ve got so many players missing at the moment and we’ve still got the real heat of the season to come. The intensity of the games, what’s resting on the games — we’re not going to know what we’re left with until right at the end but we’ll just have to make the best decisions we possibly can. There’s so many unknowns at the moment in terms of who might be available.”

There are still questions to answer. England have not improved their record against FIFA’s top-10 ranked nations. Concerns linger about England’s defensive durability, particularly at center-back. Stones and Maguire look certain to be Southgate’s first-choice pairing for a fourth consecutive tournament, but are they good enough and are the understudies a considerable drop off?

Kane’s absence was felt less against Belgium than Brazil, meaning Toney advanced his case better then Ollie Watkins managed last weekend. But arguably England’s biggest issue dating back a long time has been a lack of midfield control against the best teams. It would be premature to declare Mainoo as the answer, but a camp of surprises has thrown up a welcome consideration.