Manchester United captain Antonio Valencia insisted he is “fully supportive” of Jose Mourinho after appearing to back calls for the under-fire manager to leave.

All is not rosy at Old Trafford and a winless run stretched to a fourth game on Tuesday as Spanish visitors Valencia held United to a 0-0 draw in the Champions League.

Struggles on the field are compounded by issues away from it, with reports that skipper Valencia is not seeing eye-to-eye with Mourinho fuelled after the game.

The 33-liked-old ‘liked’ an Instagram post from a fan account which said that “recently Mourinho has made watching us a punishment” and “it’s time for Mourinho to go”.

Wary of the media scrutiny it had caused, as well as the manager’s argument with Paul Pogba about social media last week, Valencia attempted to explain and apologise on Wednesday morning.

“Yesterday, I liked a post on Instagram without reading the text that accompanied the picture,” the right-back wrote on Twitter.

“These are not my views and I apologise for this. I am fully supportive of the manager and my teammates.

“We are all giving our everything to improve the results.”

Tuesday night was just Valencia’s fifth appearance of the season, having been omitted from United’s previous two squads.

It is reported that Mourinho dropped the full-back for Saturday’s 3-1 loss at West Ham after criticising him for not attending the Carabao Cup exit to Derby, with the pair said to be barely on speaking terms.

Asked after Tuesday’s game about his relationship with the United boss, Valencia said: “I have never had any problems with anyone, thanks be to God.

“The decision is up to the manager and you’ve got to respect it.”

Attention now turns to Saturday’s crunch Premier League visit of Newcastle, with Valencia underlining that United “have to fight”.

But Mourinho has questioned his players’ attitude this week, suggesting his team did not lose with dignity at West Ham after saying some of them care more than others.

“I can say that in the dressing room, the guys are calm and everyone is working hard every day with the right attitude,” Valencia added.

“People are saying things because we’ve not necessarily got results, but everything is good, there’s not a problem.

“Everything will calm down when we get some wins. We are 100 per cent behind the manager.”