London: Louis van Gaal is adamant David de Gea can still get better despite witnessing the Manchester United goalkeeper produce a superb performance in the 2-1 Premier League win against Arsenal.
The Spanish number one kept the Gunners at bay with a man-of-the-match display at the Emirates to propel United into the top four for the first time this season.
De Gea made vital saves throughout to deny Jack Wilshere, Alex Oxlade-Chamberlain, Santi Cazorla and Alexis Sanchez before Olivier Giroud`s stoppage-time consolation in north London.
Yet, although De Gea`s heroics combined with goals from Wayne Rooney and a Kieran Gibbs own goal gave United victory, Old Trafford boss van Gaal claims the best is all ahead of the 24-year-old stopper.
"I think they were shots from outside the 60m. I have also played and when it is outside the 60m the goalkeeper has more benefit than the player," said van Gaal.
"His quality is exactly on the line. I`m used to this quality. But he also has to improve in other aspects of the game.
"When I say that then you think I am crazy. But I am not crazy, believe me."
Van Gaal was unimpressed by United`s performance, despite a first away win of the season, and highlighted the ease at which they conceded possession to Arsenal, particularly in the opening 20 minutes.
The Dutchman, whose side now face winnable home games against Hull and Stoke, added: "I have to say the first 35 minutes we gave the ball away so easily that it`s not possible for a top team. Because of that, Arsenal created a lot of chances.
"Fortunately we have a very good goalkeeper and after the first 35 minutes you saw that we are coming back in the game and created a few possibilities.
"But I said at half-time. When we keep the ball, when we show confidence then we shall create many chances.
"We created at least three big chances. (Angel) Di Maria could finish the game also.
"But also twice the pass was easy to give to Di Maria and Wayne Rooney and the pass was not right.
"That was not a difficult pass in my opinion so we have to improve that."
For Arsenal, the loss means they have made their worst start to a season in 32 years after dropping to eighth.
Midfielder Jack Wilshere was fortunate to escape action from referee Mike Dean for an apparent headbutt on Marouane Fellaini.
Arsenal boss Arsene Wenger claimed he did not get a clear view of the first half incident.
"I haven`t seen it because it was on the other side and I haven`t seen what happened there well enough. Overall it was a fair game, physically committed but I didn`t see any bad things on the pitch," he said.
Yet Wenger was crystal clear on his opinion towards the Gunners defence, labelling their performance as "naive".
He added: "We were not efficient enough in the final third, defensively and we made a mistake at the back which they took advantage of. That`s the history of the game. We had plenty of chances.
"You have to be efficient in top-level games and we were not efficient enough in our good periods, but there were a lot of positives in the game.
"Even if we are very, very disappointed, we have to keep that and rectify. At the moment defensively we are a bit naive. The second goal was just after a corner and we were not cautious enough.
"I don`t know why we had nobody at the back at all -- you could see straight away that giving a two against one in your own half means you will be punished against these players."