In the opinion of many football fans, David de Gea confirmed his status as the best goalkeeper in the world on Saturday.

The Spaniard made a remarkable 14 saves against Arsenal - some of them absolutely stunning - to help Manchester United win 3-1 at the Emirates.

He’s certainly come a long way since arriving at Old Trafford as a timid 20-year-old back in 2011.

United showed great faith in De Gea after he arrived for £19 million from Atletico Madrid.

At first, he struggled with the physicality of the Premier League and nobody could have predicted how he would develop into an absolute monster of a goalkeeper.

But Sir Alex Ferguson had faith.

Ferguson missed a Man Utd match to scout De Gea

And following on from his performance against Arsenal, the story of how Ferguson signed De Gea has emerged - thanks to former Man Utd goalkeeping coach, Eric Steele.

Writing in the Daily Mail, Steele explained how Ferguson even missed a United match to go and scout the young ‘keeper before managing his development perfectly.

"I can only remember Sir Alex Ferguson missing two United matches. He missed a Manchester derby in 2000 for his son’s wedding. The other time? To scout the brilliant David de Gea,” Steele revealed.

"I was convinced that a 19-year-old De Gea was the right man to replace him. I showed a three-minute DVD compilation to Sir Alex and then we went to watch him play for Atletico Madrid at Valencia on the night United played Scunthorpe in the League Cup.  

"Sir Alex knew he was the right signing inside 65 minutes. David showed composure, concentration and reflexes. He made one terrific save that went through a load of bodies.

"People targeted David physically but we never changed our programme to improve him. We knew the strength and power would come. Sir Alex and I encouraged him the whole time. Sir Alex did not criticise him. Not once. He left him out at some stages and put him back in but he never shouted at him or put him down.

"And just look at David now! His outstanding quality has always been his calmness and on Saturday night, amid all the penalty-box mayhem, he was a beacon of tranquility. He is the calmest man on the field."

You know a player is special if Ferguson is willing to miss a Man Utd match to scout him.

Steele and his scouting team deserve credit for discovering De Gea but Ferguson certainly played a large part in his development as a player.

Yet another reason why he’s one of the greatest managers football has ever seen.