Martial's goal drew comparisons with former Arsenal striker Thierry Henry

Anthony Martial: Louis van Gaal praises Man Utd teenager's impact

Manchester United boss Louis van Gaal said Anthony Martial's debut goal in their 3-1 win over Liverpool came after impressing in his first few days.

Martial, 19, was signed for £36m from Monaco, making him the world's most expensive teenage footballer, and was named as a substitute at Old Trafford.

Van Gaal said: "He made a very good impression in the first three days, that's why I selected him on the bench.

"When you make a goal like Anthony you cannot wish for more, I think."

Martial's 86th-minute goal in Saturday's win came two minutes after Christian Benteke had pulled a goal back for Liverpool with a spectacular bicycle kick.

The teenage substitute waltzed around Martin Skrtel before slotting into the far corner at the Stretford End, sending Old Trafford wild.

Van Gaal had previously admitted that the pressure to succeed was higher at Manchester United than at other clubs, citing the likes of Angel Di Maria and Radamel Falcao, who were signed last season.

But despite the debut goal, the Dutchman said it was too early to judge whether Martial could live up to it the hype.

"A lot of players have made a debut and scored with me so it's a good signal," Van Gaal.

"We scouted him and we wanted him because he's the best in his age, but he needs time and three days is too short to judge his personality."

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The victory came after rumours of dressing room unrest, with skipper Wayne Rooney and Michael Carrick telling the Dutch boss prior to the game that the atmosphere amongst the squad was flat.

Rooney was absent with a hamstring injury, with Van Gaal saying that the England captain – who broke the England scoring record against Switzerland last week – could be a doubt for Tuesday's Champions League trip to Dutch side PSV Eindhoven.

Van Gaal added: "I don't think he should play on Tuesday, we don't want to take any risks with our captain but you never know. It's Saturday and we still have Sunday and Monday."

The Manchester United boss also said he took off Memphis Depay for "tactical reasons". The former PSV forward, who signed for £31m in June, was replaced at half-time by Ashley Young.

"In the third and fourth phase, he could have played the last pass better," said Van Gaal.