David de Gea headed into this season off the back of a disappointing World Cup.The goalkeeper had made mistakes aplenty in Spain's campaign in Russia, where they were knocked out in the last 16.But De Gea put that disappointment behind him at the start of the campaign for Manchester United.While United were struggling under Jose Mourinho, De Gea was one of the club's most reliable performers.In a 2-1 win over Leicester City on the opening day of the season, De Gea produced fine stops from James Maddison and Damarai Gray to ensure the club got off to a winning start.

He then turned in another Man of the Match performance a few weeks later, with his saves helping United to a narrow 2-1 victory v Watford.

But, despite his early season form, De Gea has come under criticism in recent months.

In December, in a match against Arsenal, the Spanish goalkeeper made an uncharacteristic mistake when he failed to stop a header from Skhodran Mustafi.

De Gea was again the culprit as Arsenal secured a 2-0 win over Manchester United in March.

Granit Xhaka's long range strike managed to beat De Gea despite going no where near the corner.

News about De Gea's contract issues had circulated around that time and Gary Neville theorised that was the reason for his mistake.

"It was really poor from David De Gea. I'm not sure how to explain that. He hits it well Xhaka," Neville said on Sky Sports, per the Mirror.

"He's got a clear sight of it. It swerves but I've got no defence for him. It's poor from the goalkeeper.

"All the noise of the contract. He must have had a lot of noise in his ear."

And De Gea has been under even more scrutiny following United's loss to Wolves on Tuesday night.

De Gea looked shaky throughout and he was partially to blame for Wolves' winner.

The ball bounced off Chris Smalling and De Gea put in a half-hearted attempt as he failed to prevent the ball trickling into the net.

Watch it below:

While that goal isn't entirely his fault, some United fans have now turned on De Gea.

It's true that De Gea's performances have declined in the second half of the season.

Perhaps there is an argument that his contract issues are playing on his mind.

However, most criticism that he is receiving at the moment is unjust.

During Jose Mourinho's final few months at the club, there is no doubt that De Gea was United's best performer.

He saved the team time and time again in the opening half of the season and single-handedly won them points.

In all, De Gea has made 106 saves in the Premier League this season.

That puts him second in the league, only behind Lukasz Fabianski.

11 of those saves came in a 1-0 win against Spurs in January, where De Gea's brilliance ensured United picked up all three points.

United's defence has been suspect throughout and De Gea has been called into action more than the average goalkeeper.

Despite being overworked, according to the official Premier League, he has only made two errors leading to goals.

That's one less than Alisson Becker has made at Liverpool; and he has been heavily praised this season.

As things stand, De Gea has won United a lot more points than he has lost them and that's the bottom line.

He is still the best goalkeeper in the world despite his recent performances.

There is cause for concern if his form continues to spiral. 

But for now, any criticism directed at him is quite simply unjust.