In a lot of ways, there was not much more Manchester United could have done to reach the Europa League final on Sunday, but they nonetheless succumbed to a 2-1 defeat to the competition's almost perennial winners, Sevilla.

United played a lot of good football and were the greater threat in attack – but while they were routinely thwarted in the Sevilla penalty area, they were their own worst enemy at the other end and in the dugout.

Ole Gunnar Solskjaer's men follow their Manchester rivals City out of Europe 24 hours later and they will have a similar feeling of regret despite a great start in Cologne.

In fact, Solskjaer's selections made perfect sense. The choice of Fred in midfield instead of Nemanja Matic, while initially surprising, was by no means without merit.

Those who can recall the last time these two met will surely understand why, with Matic part of a midfield that was dominated by Sevilla's Ever Banega – the Spaniards winning 2-1 at Old Trafford to knock United out of the Champions League last 16 in 2017-18.

Fred's role would seemingly be to harry Banega and stifle Sevilla's creativity in the middle, and although the extra dynamism offered by Fred could certainly be noticed at times in the first half, it's difficult to say he nullified Banega, who completed 49 of his 50 passes before the interval.

The Argentine playmaker, who is set to move to Saudi Arabia at the end of the season, offered plenty of class for the Spaniards, but ahead of him – perhaps bar their first goal-scorer, Suso – few others were on a similar wave length.

No, in the end, for all the attention on the like of Banega and Lucas Ocampos, the main men for Sevilla were arguably two of the most unlikely.

Having been frustrated for a long time by Copenhagen goalkeeper Karl-Johan Johnsson in the quarter-finals, United's forwards will surely have been baffled by another outrageous performance between the posts.

This time Yassine 'Bono' Bounou was stellar in the Sevilla net – the Morocco international a stand-in for usual first-choice Tomas Vaclik, who missed the LaLiga run-in through injury.

While he was helpless for Bruno Fernandes' penalty, Bono went on to make six saves, several of which came in a ferocious flurry at the start of the second half.

Anthony Martial twice had what looked like certain goals denied, while Mason Greenwood forced Bono into his best stop.

As United faded after that, there was an air of inevitably about the eventual outcome, though Solskjaer could have done more.

For the most part, Solskjaer and his counterpart Julen Lopetegui were well-matched. It was a fascinating tactical battle for a long time, as United looked to exploit the spaces behind Sevilla's full-backs, who at the same time were generally Los Nervionenses' liveliest players in attack.

But where Lopetegui came out on top, thus giving Sevilla the edge, was with his substitutions. Ocampos and Youssef En-Nesyri came off before the hour, while they made three changes before United even made one.

You couldn't even say they would've been popular changes either – Ocampos is their top-scorer, while En-Nesyri's replacement, Luuk de Jong, has been one of the most-criticised players in Spain this season. He hadn't scored in his previous 11 appearances.

It was then telling how decisive those alterations were. Two of Sevilla's subs were involved in the winning goal. Franco Vazquez – brought on three minutes earlier – found Jesus Navas, and his cross was turned in by, you guessed it, De Jong.

United's defending for the winner will be debated for days, it was that poor. Brandon Williams should've done better against Navas, who was only ever going to cross right-footed, while Victor Lindelof and Aaron Wan-Bissaka let De Jong escape.

But had Solskjaer reacted earlier, the end result may have been significantly different. The overriding realisation was how little trust the Norwegian has in his fringe players, and not for the first time this season.

This defeat doesn't have to mean it's all doom and gloom for United from here. After all, Liverpool suffered Europa League disappointment to Sevilla in the final a few years ago, but they built on what was a promising run in the competition by making smart acquisitions – now look where they are.

But United must learn from this, and first and foremost those lessons should influence them in the transfer market.

If Solskjaer doesn't trust his back-up players, United's squad suddenly appears even shallower than many of us think. He needs squad options that he can depend on, players he feels can make a difference.

A little well-placed trust can prove decisive – just ask Lopetegui and De Jong.