Ole Gunnar Solskjaer's Manchester United side fell 4-0 on aggregate to Barcelona after losing 3-0 at the Nou Camp

Manchester United have now lost five of their last seven games - a decline that started immediately after their heroics in Paris.

Lionel Messi produced a customary masterclass at the Nou Camp on Tuesday evening, scoring two goals as Barcelona dumped United out of the Champions League 4-0 on aggregate.

Solskjaer was named permanent manager just three weeks ago, on the back of two straight defeats against Arsenal in the Premier League and Wolves in the FA Cup.

It's been a big struggle since the PSG game, and in some ways I'm happy, because I think if United had carried on as they were towards the end of the season, I think it would have conned and fooled everybody into thinking it was okay. Gary Neville

But the vote of confidence and an international break failed to reverse a rapid decline in form, which has seen United's returns regress to numbers recorded under Jose Mourinho earlier this season.

United's win percentage in all competitions is currently at a monthly season low at 25 per cent, having only won one of their four games in April so far - a stark contrast to the season-high 83 per cent in January.

The graphic below shows United's average number of goals scored and conceded in the Premier League during this campaign - revealing the immediate impact of Solskjaer's appointment as interim manager in December.

But that rate peaked with a 4-1 win over Bournemouth in their final game of last year and has been on the wane since, currently averaging at pre-December levels.

However, despite clear indications the honeymoon bounce effect is over, there are positive signs United are still producing a superior number of chances under their new manager.

Expected goals data suggests Manchester United were unlucky to lose against Arsenal and Wolves in the Premier League recently

Expected goals data, which measures the true value of chances in front of goal, suggests United are consistently outperforming opponents under the Norwegian - having struggled to maintain surplus runs under Mourinho.

Premier League data reveals United have recorded less activity down the left channel since their extraordinary result in Paris, an area typically marshalled by Paul Pogba - who initially improved considerably after Mourinho's departure.

That decline could also be a result of Solskjaer choosing not to deploy a 4-3-3 system in the league since beating Palace in February, while tstarting three at the back for the first time during the 2-1 defeat at Wolves.

An injury crisis struck United in March with 10 players sustaining 13 injuries, according to physioroom.com - including Ander Herrera, Nemanja Matic, Anthony Martial, Eric Bailly, Luke Shaw, Marcus Rashford and Romelu Lukaku.

As a result, Solskjaer made at least four line-up changes in three out of four top-flight games that month.

The graphic below reveals the Norwegian has been shuffling the pack again recently, making six changes in the league defeat at Wolves - attempting to manage European commitments, rekindle form and reintroduce fit-again players.

The graphic below shows which players Solskjaer used most before and since their victory in Paris.

Notable absentees include Matic and Herrera, key holding midfielders who have been left out of the squad recently after returning from their injuries, while Fred, Diogo Dalot and Chris Smalling have been used more frequently.

Ander Herrera has been linked with a move away from Old Trafford this summer

The most notable statistical dips since the victory in Paris have been a severe decline in shots on target and, as a result, goals.

Interestingly, United have actually recorded higher averages across a raft of defensive metrics since their quarter-final heroics - areas typically associated with Mourinho's tenure at the helm.

Conclusion

Solskjaer was appointed on a permanent basis only five games ago, but the honeymoon period does, indeed, appear to be over after experiencing a remarkable bounce effect following his initial arrival in December.

United's points-per-game ratio, in addition to their goals scored and conceded rates, have regressed to Mourinho levels - but the quality of their chances have been consistently higher under the Norwegian.

Pogba was one of the most improved players after Mourinho was axed, but the World Cup winner has recorded less activity in the Premier League over the past few weeks in his favoured areas.

Paul Pogba scored two penalties in the 2-1 win over West Ham on Saturday, having gone six league games without scoring

Meanwhile, Solskjaer has experimented with several different systems over the last four league games and has started with three centre backs for the first time this term in the league - which has boosted defensive stats.

Ultimately, the stats were regressing before the injury crisis hit last month, but United do appear to have missed Herrera and Matic - with Fred collecting more game-time in their absence.

But, despite the limp exit from Europe in Barcelona, all is not lost for Solskjaer.

In the Premier League, United remain only two points shy of fourth-placed Arsenal with five games still to play. So his team will now focus on a top-four finish to go again next season after the promised 'rebuild' begins this summer.

We have a rebuilding job. It started with coaches, players and of course one or two additions in the summer. Ole Gunnar Solskjaer

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