Manchester United legend Gary Neville claims there is "something wrong" with Anthony Martial as he believes the France international is "playing at 85 per cent".
The 21-year-old moved to Old Trafford from AS Monaco in 2015. After impressing in his debut season, the forward struggled under Jose Mourinho last season. However, he has bounced back with six goals and five assists in all competitions this term.
Martial came off the bench and scored the winner in the 20-time English champions' 1-0 victory over Tottenham Hotspur at Old Trafford. He scored all his four goals in the Premier League after coming off the bench.
Mourinho has rotated Marcus Rashford and Martial this season, with the latter replacing the England international in the 69th minute in their latest win over the north London club. Neville remains confident the Frenchman can go on to become a world class player, if he "showed that extra 15 per cent".
"It's been a stop-start Manchester United career for Martial. For someone of his talent, he should be tearing this league apart with his ability. He's lost his place in the France squad - there's obviously something wrong with him," Neville told Sky Sports.
"Mourinho and the French manager has turned off of him a little bit. You always get the feeling he's playing at 85 per cent. If he showed that extra 15 per cent, then he could do anything. He's got everything you'd want: composure in front of goal, great skill, pace, strength, but what is that little bit missing?
"The best players in the world don't have 'but's' - the likes of Luiz Suarez, Cristiano Ronaldo, Lionel Messi - there are no buts. Martial is well off that category but that's where he's got to be looking.
"He's worth £50million and with that talent, he's got to step up. He scores in big games, he takes big moments on and obviously has the temprement to play in big games. But come on, let's see it every single week.
"He could be a player that could score 20 goals in 20 games if he really wanted to and strived to be the best."