Alexis Sanchez is struggling to make an impact at Manchester United due to Jose Mourinho's restrictive style, according to Paul Merson.

Sanchez last found the net for Manchester United against Tottenham in the FA Cup on April 21, more than six months ago and nine games ago.

And Merson believes the free-flowing style that allowed Sanchez to thrive at Arsenal means his games game is restricted at Man United.

Alexis Sanchez is struggling for his best form at Manchester United, according to Paul Merson

On Sky Sports' The Debate, Merson said: 'He looks a bit lost at the moment, but that could be confidence,' Merson said. 'I can't believe it's nearly six months without a goal. For someone who is supposed to be that good, that's a long time as a forward.

'He's struggling at Manchester United. They don't make as many chances as Arsenal. Arsenal are all-out attack but that's not the way they play at Old Trafford. When Arsenal play, they just go gung-ho, that's not the case at Manchester United.

ALEXIS SANCHEZ AT MAN UNITED SEASON APPS GOALS 2017/2018 18 3 2018/2019 5 0

'At United, there's a structure and they say 'let's not get beat first and then go from there'. That's why I think he's finding it difficult. At Arsenal, it was free-flowing but it wasn't successful, they didn't win anything.'

Merson also highlighted the different environment as reason for the struggle, with Sanchez competing against the likes of Paul Pogba and Romelu Lukaku for the leading role at Old Trafford.

He added: 'It's the pressure. When he was at Arsenal, he was the top man. Everything went through him, plus he could try things at Arsenal. He could flick a ball here, flick a ball there and if it didn't come off, you were playing next week. That is not the case at Old Trafford.

Jose Mourinho's style could be holding Sanchez back from truly thriving at Old Trafford

'With Jose Mourinho, we saw what he was at Chelsea with Eden Hazard, if you are not getting back and following the full-back back, you're off and you're not playing next week. That didn't happen at Arsenal.'

There is also increased competition at Old Trafford, with Marcus Rashford waiting in the wings for a chance.

'You are keeping out a young talent in Marcus Rashford,' Merson added.

'But Rashford did play last week in Europe, and he didn't really shine. Mourinho then has a case of saying 'you didn't really turn it on in that game'.

'It is a problem giving him big wages. I don't know if Man Utd wanted him. I think it was a case of there's nobody else around, so we'll take him so Man City can't have him and it's backfired in a way.'