Listen to the full interview on BBC Five Live from 1900 GMT on Tuesday 7 February

McClaren told BBC Radio Five Live: "Yes there's an unhappy dressing room - we're losing matches.

"I would not expect the dressing room to be happy but there's a great spirit.

"Greening's comments disappointed me because he did well at this club. He came from Manchester United reserves and I gave him an opportunity."

Greening, who left Boro for West Brom in 2004, told the Daily Mirror newspaper: "I am not really surprised to see Middlesbrough struggling.

"I know a few of the boys there who are a bit unhappy with McClaren's way of doing things."

McClaren came under renewed pressure following Saturday's 4-0 capitulation at home to Aston Villa.

That left the club one place above the relegation zone and led to increased speculation that McClaren could lose his job.

Boro to stick with McClaren

Boro chairman Steve Gibson is standing by his manager but McClaren is conscious of the pressure.

"I'm a winner and we're losing too many games," he said.

"That disappoints me, upsets me and puts pressure on me. I am results-orientated and of course there's speculation when we're not getting results."

Middlesbrough's next game is Wednesday's FA Cup replay against Coventry.