Manchester United are still in need of a winger to "complete" their squad, according to former defender Gary Neville. Jose Mourinho's side began their campaign with an emphatic win over West Ham United on the opening weekend - with new signing Romelu Lukaku scoring twice on his Premier League debut for the club - but there remain areas in which they can improve.

Mourinho has made no secret of his desire to sign a fourth player during the remaining weeks of the summer transfer window. A wide player is thought to be among his preferred targets, with Ivan Perisic and Gareth Bale having both been linked with moves to the 20-time English league champions.

But while speculation regarding a move for Perisic has quietened in recent weeks, Mourinho has already given up in attempts to sign Bale after he played against his United team in the Uefa Super Cup defeat to Real Madrid.

But nonetheless, Neville feels someone - in the mold of Bayern Munich's Arjen Robben, who is formerly of Chelsea - who can fill the role on the left side is still needed.

"I'd name a player similar to Arjen Robben - a wide player," Neville, an eight-time Premier League winner with United, told Sky Sports. "[Marcus] Rashford did very well today but is he a wide player? Not really. I'm talking about someone who can generally play left side. If you could add one world-class winger to add to the squad you could say it was a complete squad... they are covered everywhere, they have such strength."

Among the stand-out performers in United's 4-0 win, delivered by a double for Lukaku and late goals from Anthony Martial and Paul Pogba, was another new addition – Nemanja Matic following his move from Chelsea. The Serbian patrolled the midfield with authority throughout, giving the likes of Pogba and Juan Mata license to influence the game in the final third.

Neville has previously spoken of his surprise over Chelsea's decision to allow Matic to leave and the ex-England international remains flabbergasted following his impressive debut. "You cannot believe Chelsea have given Mourinho a piece of the jigsaw in Matic," he said.

"I can't think of one reason why Chelsea sold him. United beat Chelsea to Lukaku and then Chelsea have handed them Matic. They look like the type of players that were needed to correct what was wrong last season, and Chelsea have helped them and had a big influence on that."

Jose Mourinho
Mourinho is on the look out for a fourth summer signing. Getty Images