David De Gea, the one-time winner of the Premier League's Golden Glove award for the season's best goalkeeper, has seen a sharp decline in form over the last two years. He was voted as the best shot-stopper in the English top-flight at the end of the 2017-18 campaign, but post that his performances have been highly irregular between the sticks.
Though he can be a gem of a goalkeeper on his day producing remarkable saves from insane reflexes, it's the ability to do so consistently that has taken a hit. This poor run of form has also caught up with him during international duty that has seen him lose his spot in the Spain national team to Chelsea goalkeeper Kepa Arrizabalaga.
So, with the Spaniard going through one of the worst spells of his career at the Old Trafford, we take a look at five of the biggest mistake by the league's top-paid goalkeeper that eventually cost his side the game.
#5. Manchester United 2-2 Arsenal; 8 December 2018; Goalscorer- Shkodran Mustafi
De Gea's mistake against one of Manchester United's greatest rivals Arsenal in the 2018-19 season came at a moment when things were starting to go south for Jose Mourinho at Old Trafford. In the 14 games leading up to this game, the Spaniard had only kept two clean sheets and The Red Devils were without a win in their last three games.
In the game that ended in a 2-2 draw, De Gea's error led to the visitors breaking the deadlock in the 26th minute of the game when defender Shkodran Mustafi found the back of the net from a routine corner capitalising on the goalkeeper's howler.
The headed effort should've been easily saved by De Gea but he made a mess of it and the ball passed right through his palms and handed Arsenal the lead. Though the game ended in a draw, it would've been a completely different story if not for De Gea's fault.
#4. Arsenal 2-0 Manchester United; 10 March 2019; Goalscorer - Granit Xhaka
The last few game weeks of the 2018-19 season were particularly tough for De Gea. He failed to keep a single clean sheet in the final 11 matches of the campaign and committed three major errors leading to goals in just seven games between March 10 and April 28.
The first in the series of these high-profile mistakes came against a familiar opposition in Arsenal when Granit Xhaka managed to beat the Spaniard from 25-yards out.
The Swiss international unleashed one of his trademark long-range strikes from his left-foot and though it swirled mid-air, De Gea could see it coming in all the way; the 29-year-old completely misjudged the flight of the ball and could only watch as it whizzed past him.
#3. Everton 1-1 Manchester United; 1 March 2020; Goalscorer - Dominic Calvert-Lewin
The former Atletico Madrid No.1's latest mistake was probably one of the most ridiculous errors expected from a goalkeeper of the calibre of De Gea. Somehow he managed to make a mess of a back-pass and gifted Everton the opening goal after his poor clearance cannoned straight into Dominic Calvert-Lewin and then into the net just three minutes into the game.
It was a dreadful lack of concentration from the Spaniard that cost United the three points from the game, setting them back very early only to be saved by a goal by Bruno Fernandes in the first half.
#2. Portugal 3-3 Spain; 15 June 2018; Goalscorer - Cristiano Ronaldo
De Gea drew scathing criticism from Spain's supporters in their 3-3 draw against their fierce rivals Portugal at the biggest stage of world football, the FIFA World Cup in 2018.
Cristiano Ronaldo scored all of Portugal's three goals in the game, including a brilliant last-gasp free-kick but it was his second goal in the 44th minute that puts De Gea into the spotlight.
The Manchester United keeper made a terrible and uncharacteristic error, fumbling a speculative Ronaldo shot through his gloves and over the line.
#1. Watford 2-0 Man United; 22 December 2019; Goalscorer - Ismaïla Sarr
One of the most embarrassing mistakes committed by De Gea during his time with the Red Devils in recent memory came against the then bottom-placed Watford in the ongoing Premier League season.
The 29-year-old let Isamaila Sarr's mistimed effort from close range following a free-kick literally slip through his palms and handing the underdogs a lead in the crucial fixture.
It will go down as one of the most forgettable moments of his career and we can only hope that he does not succumb to making such mistakes from now on.