Under-fire Newcastle manager Sam Allardyce on Monday blasted controversial midfielder Joey Barton for letting him down.

Barton will see in 2008 in prison after being charged with common assault and affray following an incident in Liverpool over the Christmas period.

And Magpies boss Allardyce, who spent out 5.8 million pounds to take the midfielder to St James' Park, revealed his frustrated at Barton's behaviour.

He told the Daily Mirror: "Yes, I feel let down by him, of course I do. There's no question about that but I' ve got to deal with that quietly and privately when the opportunity arises."

Allardyce has spoken to Barton since he was remanded in custody but insists his future at Newcastle has not been discussed.

"I have spoken to him but I'm not going to tell you what was said. The Joey Barton situation is something we had to put behind us because we've got so many games in such a short period of time," said Allardyce.

' We’ll deal with that later on and find out what the outcome is when I get the opportunity with the chairman.

"It's disappointing, very, very disappointing but I can't really comment any further than that."