Rafael van der Vaart has criticised Erik ten Hag for his reluctance to use Casemiro since the Brazilian's £70m arrival from Real Madrid at the end of the summer.

Casemiro was once again a substitute as Manchester United succumbed to a heavy defeat at the hands of their rivals Manchester City in the derby on Sunday. 

Joining an ever-growing cast of former players to have criticised Ten Hag's team selection, Van Der Vaart said his compatriot had created a rod for his own back in not throwing Casemiro in from the start. 

Rafael van der Vaart criticised Erik ten Hag's use of Casemiro since he arrived in the summer

'Ten Hag should have started playing Casemiro straight away,' Van Der Vaart told Dutch television station Ziggo Sport. 

'McTominay starts performing and Man United start winning and then of course he can’t put McTominay out of the team anymore. I find this very stupid from him because you are creating your own problem,' he added.

With United 4-0 down at half-time, Casemiro's opportunity to come on and greatly influence the game had long since passed.

Eventually introduced on the hour mark for McTominay, United enjoyed a slight resurgence in the second half - winning it 3-2 - but any chance of laying a meaningful glove on Pep Guardiola's side had been extinguished through being 4-0 down at the break. 

Rio Ferdinand on Monday critiqued Ten Hag's use of the Brazilian, saying that Casemiro could feel 'disrespected' by his so-far bit-part role at United. 

'The geeze (sic) hasn’t been given a chance, he hasn’t been given a fair crack of the whip. He’s come in and played in a Europa League game against some dead team,' he told

‘He ain’t been given a start in the team when he’s fit and ready, he’s regressed in terms of fitness, so he’s now worse off than when he came. He still had to get up to speed when he came from that league to this league.

‘I wonder the impact it’s having on someone like him. Yes he’s experience and whatnot, but he must be sitting there thinking, "wow, I’m happy to be here at Man United but I’m feeling a little bit disrespected here, given what I’ve done". I’d be surprised if he’s not feeling like that.

'He’s sitting there going, "I’ve won five Champions Leagues with this team (Real Madrid),"' he said.

However, Ten Hag defended his decision not to introduce Casemiro, explaining: 'On the day we signed him, we started to win and it's about the team. The team is doing really well, it's not against Casemiro, it's for, in this case, Scott McTominay.

'He performed great in the team and then we get into a run, but I'm sure it will be important for us in the long and short-term. He will find himself in the team but it has to come in a natural way.'  

Ten Hag will be aware of the growing list of pundits lining up to criticise his selection decisions. 

Roy Keane, speaking on Sky Sports in the immediate aftermath of United's evisceration at the Etihad, said that the Dutch manager was 'disrespecting' Cristiano Ronaldo by not playing him. 

'I think Man United are showing disrespect to Ronaldo. I think he should have been let go before the [closing] of the window,' the former United captain said. 

'Okay, you're the manager, you need options but you don't hold onto Ronaldo to sit on the bench. He's one of the greatest players ever.

'He's played him in one or two European games. It's just going to get uglier as the season goes on. 

'If he's sitting on the bench for United, week in, week out it's just going to get uglier. I think United have shown nothing but disrespect to Ronaldo.'