Martial kept his place in the No.9 role for Man United and displayed some brilliant centre forward play, holding the ball up well and getting others involved.
He also showed off his pace and his ability to beat a man on numerous occasions, most notably to set up Wayne Rooney for the captain’s first Premier League goal of the season.
Van Gaal called him “an attacking point” as the Frenchman gave United so many options throughout the afternoon.
Speaking about the match, van Gaal said: “We scored again beautiful goals so I’m a very happy coach. A very good result, top of the league.
“Martial was one of the main keys to why we have won this game. He’s not only a goalscorer but he’s an attacking point.”
Martial was willing to receive the ball with his back to goal, as well as make runs in behind the centre-backs. He was happy to take players on and his pace found him causing all sorts of problems for the Sunderland defence.
The manager was delighted that his side are top of the league after Manchester City lost 4-1 to Tottenham Hotspur earlier in the day. It means United have a one point lead at the summit and van Gaal felt that a lot of the reason for that was down to Martial.
The 19-year-old has been scoring goals for fun since his deadline day move from Monaco but was equally as impressive today, despite not getting on the scoresheet. He will want the opportunity to improve on his scoring record against Wolfsburg in midweek but, at just 19, United will need to be wary about his development.