Despite dominating with 75% possession and 33(!) shots at goal, Arsenal slumped to a shock 3-1 defeat at home to Manchester United on Saturday evening.It really was all one way street at the Emirates Stadium, but the fact of the matter was the Red Devils were more clinical going forward.And not to mention that United goalkeeper David de Gea was in the form of his life.Fourteen shots saved equalled a Premier League record set by Tim Krul for Newcastle United in 2013 and Tito Mannone for Arsenal against Chelsea in 2014.Indeed, Jose Mourinho nailed it after the game when he said he told De Gea that he was watching the best goalkeeper in the world right now."I told him after the match: what I saw was the best goalkeeper in the world," Mourinho told reporters. "In big matches you want your keeper to be there for you."And be there De Gea was. Bar the Alexande Lacazette goal, Arsenal's players simply couldn't beat the Spain No.1.His double save to deny Lacazette and Alexis Sanchez was stunning, parrying the former's close-range strike and then somehow using his foot to block the latter's follow up.Safe to say every football fan has been talking about De Gea's display since the game and now a tweet is going viral that perfectly sums up just how good he is.

It reads: "David de Gea could save a PDF file on a calculator."

Simply put, De Gea is capable of the impossible when he's in goal. The tweet has received over 35,000 retweets and 23,000 likes, such is how perfect it is.

Even Arsene Wenger was forced to admit in his post-match press conference that De Gea was a rock in goal.

"I am really disappointed because it was a good performance," said the Arsenal manager. "I feel sorry for the players that gave so much but had nothing to show for it.

"But we had nothing to show for it at the end and that is hard to take. We weren't efficient enough in the areas where it matters. We put ourselves in difficult positions.

"It was not even huge pressing, we didn't have enough in dictating our fight from the start. Their goalkeeper was absolutely outstanding.

"I am proud of their commitment and attitude, I feel sorry for the players that gave so much but had nothing to show for it with points at the end."