Roy Keane scathingly described Manchester United as playing like a 'load of strangers' and jested Anthony Martial is consistently let off by 'scoring a goal every 14 years'.
United were outperformed against Newcastle on Saturday with Erik ten Hag's side failing to match the intensity of the hosts at St James' Park as they slumped to a 1-0 defeat.
Martial was given the nod to start upfront in place of Rasmus Hojlund, but produced a torrid showing that eventually led to him being replaced in the second half by the younger Dane.
Keane, formerly a serial title-winning captain at United, fumed about Martial's lack of desire against Newcastle and criticised his former club for their dreadful run of results against the top nine teams in the Premier League.
Analysing their recent showing in the north east, Keane explained that Martial is not good enough to play for United and suggested the Frenchman isn't good enough to play in the English top-flight.
Roy Keane gave a scathing review of Manchester United's performance against Newcastle on Saturday
Keane highlighted Anthony Martial's performance and suggested the player isn't good enough for the Premier League
United's defeat at Newcastle means they still haven't beaten a top nine team away from home under Erik ten Hag
'Have to focus on players at the club at the moment. We mention Martial, first few touches he got last night, we forgive Martial the fact he scores a goal every 14 years I forgive a player for that,' Keane said on Sky Sports.
'But let me tell you when at Newcastle under pressure, we get that ball into you, you better get hold of that ball to get us up the pitch and a bit of breathing space.
'He's touching balls off and gives the ball away cheaply. You may as well go down the leagues.
'Man United have been trying to get rid of him a few years ago and defensively all over the shop and they seem like a load of strangers,' he added.
Keane criticised United's players and explained some individuals aren't good enough to be at the club
United boss Ten Hag has struggled to find form with his team this season with big defeats against top teams
Ten Hag's side have so far failed to win a single Premier League game away from home against any of the division's top nine teams since the Dutchman took over in summer of last year.
Heavy defeats on the road against Man City, Liverpool, Brentford and Newcastle during that time have further reinforced United's struggles against the best sides and Keane believes some players at the club can't 'deal with the demands' that playing for the English giants brings with it.
'They are showing moments against the lesser teams even though this year when beating lesser teams it's been a close call,' said Keane.
'You judge Man United on what they do in big matches, up at Newcastle even off back of European trip, that is responsibility of a Man United player and if you can't deal with demands of playing against other top teams then you aren't a Man United player and that's what your judged on,' he added.
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