Man Utd need Pogba's A-game against Barcelona after a miserable March

The Frenchman was the figurehead of the Red Devils' revival under Ole Gunnar Solskjaer but has been way short of his best form in recent matches

Football is a game of moments and Manchester United have had their fair share. 

This week marked 10 years since Federico Macheda's late winner at Old Trafford swung the title in the club's favour, and this season there's been the dramatic comeback win at Juventus and that night in Paris. 

Exalted moments are less fleeting, of course, and a good example is Paul Pogba's form in the aftermath of the departure of Jose Mourinho. 

Freed from the psychological turmoil the Frenchman appeared to suffer as a result of working under the Portuguese, Pogba flourished in the early days of the Ole Gunnar Solskjaer regime - he was the ultimate example of how United had recovered their poise.

But recent weeks have seen Pogba sink back to a level that is more reminiscent of his troubled time under Mourinho, with United’s form starting to go the same way. 

The midfielder's two-goal performance at Fulham in early February took the Red Devils into the top four - a feat that had seemed virtually impossible towards the end of Mourinho's reign. 

What's more, it was the sort of commanding performance full of swagger that showed just how vital Pogba is to Manchester United when he dominates a football match. 

Since then, the numbers paint a bleak picture. Pogba has failed to score in the Premier League and has provided just one assist .

From the start of the Solskjaer experiment to Fulham, he was averaging 0.64 Expected Goals per game and 0.24 Expected Assists. In the six league games since, those figures have fallen to 0.20 and 0.08, respectively. 

Pogba’s pass completion in the 2-1 defeat to Wolves in midweek was 70%, a seasonal low alongside the Liverpool home game, the start and current point of his slump.

One possible reason for the slowdown in Pogba’s productivity is the role handed to him by his now-permanent manager. 

Opta's player rating system identifies Huddersfield and Bournemouth at Christmas as Pogba’s best two performances of the season. Yes, they were against limited opposition at home but, crucially, these games saw the 26-year-old playing in an advanced position, almost a No.10 role, leaving him free to create and attack to his heart’s content. 

Recent disappointing performances have seen the French World Cup winner feature as part of a midfield three, however, with the additional defensive requirements seemingly a burden that has no discernible advantage for the team.

Solskjaer's time at the club has seen him vary his tactical approach considerably, for both experimental and injury-based reasons. Pogba’s strong performance away at Tottenham on the left of a midfield diamond seemed to inspire his manager to push him out wide in a midfield four away at Arsenal in March - a shape that was abandoned once the Gunners got on top. 

It's almost as though Pogba’s hugely varied skill set is something of a curse for both him and his managers: he can do a job anywhere outside of defence or centre-forward but the evidence clearly shows that he can be more productive in a much more tightly defined area.

With Real Madrid sniffing around and reports suggesting that Pogba is looking for an Alexis Sanchez-sized contract extension to stay at the club, both he and Solskjaer need to understand that he is not a versatile cog but a specialist who, in the right position and scenario, can be one of the most effective midfielders in the world.

Next up for United is the daunting prospect of Lionel Messi and Barcelona. A mountainous task but one that will be significantly more achievable if Pogba brings his A-game.

Where will he play and what impact will he have on the game? All will be revealed on Wednesday night. All eyes on Old Trafford.