The former England and Manchester United defender was full of praise for the Spaniard, while also shining a light on a particular problem he has.
Phil Neville opened up on his opinions on Juan Mata in BBC's Football Focus on Saturday, and though they were very much of a positive note, there were follow-on effects of the Spain international's quality that Neville thought may have gotten in the way during his career.
The former Everton captain felt that Mata was such a good all-round footballer, he could adequately fill in a number of positions, thus finding himself the go-to man when there was hole that needed filling and not able to stick to his preferred playmaker role.
"Juan Mata is a fantastic footballer," said Neville. "He can play in any position, but that's his problem. His best position is number 10 but at every club he has been at, he's played in every position. Now Angel Di Maria is back he has a big job to do to get Mata out of the team though.
Mata himself had admitted earlier in the program he was aware that people had questioned his role out wide in Van Gaal's 4-3-3, but felt that his performance against Liverpool more than proved he was a capable option there.
"It was one of the best days of my career [against Liverpool]," the Spaniard said. "Playing at Anfield and winning and scoring two goals it is a day I will never forget. We are playing 4-3-3 and I am playing right wing. People were saying I couldn't but you see how I played at Liverpool.
"I have had a lot of managers in my career and by the end I was always playing and had the confidence of the manager. I believe in myself more than anyone."
Against Aston Villa, Mata did indeed start ahead of Di Maria, and the former Chelsea man also played the full 90 minutes as United ran out 3-1 winners, with the Argentine instead coming on for Ashley Young, before setting up Wayne Rooney's superb strike.
But not to be outdone, Mata grabbed his own assist at the death, as he helped compatriot Ander Herrera to his second of the game.
Obviously that belief is more than justified.