Ander Herrera has "no doubt" Zlatan Ibrahimovic will recover from a knee injury so serious that some have suggested it could force the Manchester United striker into retirement.

The outspoken 35-year-old has made quite the impression since arriving at Old Trafford last summer, scoring the Wembley winners in both the Community Shield and EFL Cup final.

Ibrahimovic recently likened himself to Benjamin Button, the fictional character who ages backwards, after his 28th goal of the season - but now there are concerns time is against him.

Burnley 0 Manchester United 2 player ratings Show all 22 1 /22 Burnley 0 Manchester United 2 player ratings Burnley 0 Manchester United 2 player ratings Tom Heaton – 6 out of 10 The keeper made a multitude of vital saves, but he was beaten by both Martial and Rooney. Burnley 0 Manchester United 2 player ratings Matthew Lowton – 5 out of 10 He looked promising moving up the pitch, but defensively he was lacklustre and wasteful in possession. Burnley 0 Manchester United 2 player ratings Michael Keane – 6 out of 10 The defender done well today to keep the United attacks to a minimum. He stood his ground well and looked sharp. Burnley 0 Manchester United 2 player ratings Ben Mee – 7 out of 10 Patrolled the defensive third today – he made a handful of vital interceptions, tackled hard and worked relentlessly. Burnley 0 Manchester United 2 player ratings Stephen Ward – 5 out of 10 Struggled to keep up with the pace of the United side going forward, which made him look out of his depth against a side of such aptitude. Burnley 0 Manchester United 2 player ratings George Boyd – 6 out of 10 Boyd’s confidence was encouraging today – he looked menacing when he picked up the ball and charged at United. He forced a remarkable save out of De Gea in the early stages. Burnley 0 Manchester United 2 player ratings Joey Barton – 5 out of 10 Unlike we expect from Barton, he was giving the ball away far too often today. His passing was wasteful. Burnley 0 Manchester United 2 player ratings Jeff Hendrick – 6 out of 10 He was picking up the ball in the middle and charging into the United half confidently, which was starting the majority of Burnley moves. Encouraging to see. Burnley 0 Manchester United 2 player ratings Robbie Brady – 6 out of 10 As always, Brady’s deliveries were on point, which would have been lethal had United not been so dominant in the air. Burnley 0 Manchester United 2 player ratings Andre Gray – 6 out of 10 The striker made space for himself, ran the channels and always provided an outlet for the midfielders. Burnley 0 Manchester United 2 player ratings Ashley Barnes – 4 out of 10 You would be excused for not realising that Barnes was out there today. He looked lost and failed to make an impact on this fixture. Burnley 0 Manchester United 2 player ratings David De Gea – 6 out of 10 It was a relatively straight forward day at the office for De Gea, with very few Burnley moves going forward. Burnley 0 Manchester United 2 player ratings Ashley Young – 7 out of 10 He did well defensively, but he certainly proved problematic for Burnley going forward. He was pacey and pumped balls up to the strikers. Burnley 0 Manchester United 2 player ratings Eric Bailly – 6 out of 10 He defended well throughout, but he appeared to pick up a knock towards the end. Mourinho will be hoping that it is nothing serious. Burnley 0 Manchester United 2 player ratings Daley Blind – 6 out of 10 He stood up well when Burnley attacked, rather than just lunging into the challenges. This stopped countless moves from The Clarets going forward. Burnley 0 Manchester United 2 player ratings Matteo Darmian – 6 out of 10 Was dragged out of position from time-to-time, which allowed the Burnley wide players too much space. However, on the ball he done well and started United moves from the back. Burnley 0 Manchester United 2 player ratings Ander Herrera – 7 out of 10 He was a key element to almost every United move going forward. He assisted Martial’s opener. Burnley 0 Manchester United 2 player ratings Marouane Fellaini – 5 out of 10 He continued to give away unnecessary fouls today, which provided Burnley their best chances of the game. Burnley 0 Manchester United 2 player ratings Paul Pogba – 7 out of 10 The Frenchman ran the midfield today. He was picking up possession and pumping balls up to the forwards continuously. Burnley 0 Manchester United 2 player ratings Jesse Lingard – 7 out of 10 His excellent ability to read the game was evident. He used the width well and opened the game up, at times. Burnley 0 Manchester United 2 player ratings Anthony Martial – 8 out of 10 He was by far United’s best player today. He scored the first, assisted the second and proved himself to be a fitting replacement for the injured Ibrahimovic. Burnley 0 Manchester United 2 player ratings Wayne Rooney – 6 out of 10 The 31-year-old scored United’s second, but aside from that he played very narrow which limited the options that they had going forward.

The striker sustained significant knee ligament damage in Thursday's Europa League quarter-final win against Anderlecht and figures at United reportedly fear he may never play again.

Ibrahimovic says "giving up is not an option" and vowed to come back even stronger on Sunday evening - the kind of reaction United team-mate Herrera expected.

"Of course he can (get back)," Herrera said without hesitation.

"First because he is privileged physically. His physique, his body is one of the best I have ever seen so I think it will be easier for him to get back than others.

"But of course he is 35, he will have to work very, very hard, be very patient.

"But I have no doubt he will be back because he loves football, he loves to win, he loves to score goals.

Zlatan Ibrahimovic has rubbished suggestions of retirement after suffering a season-ending injury (Getty)

"He loves to train every day. Every day he wants to win, every box, every football tennis, everything in training, so I have no doubt he will be back.