The midfielder’s attitude was questioned early this season as he struggled to overcome the knee injury which sidelined him for the second half of last season.
But the 29-year-old is now a fixture in the starting XI.
Head coach McClaren worked with Tiote, preparing for tomorrow’s Premier League home game against Leicester City, when he was in charge of FC Twente.
And he feels Tiote is slowly getting back to his best after an injury-hit two years.
McClaren was surprised when a journalist on Sky Sports’ Sunday Supplement labelled him as a bad influence as United struggled at the foot of the division.
“Three or four weeks ago Cheicky is supposedly ‘poison in the dressing room’ – and I laughed when I saw it,” said McClaren.
“He’s the least poisonous player you can imagine. No-one has ever got a bigger smile on their face – he just wants to play.
“The staff, they don’t know him, but I know him, and they came to me the other day and said ‘my God, how hard does he work in training?’.
“Honestly you watch him. He is everywhere. He’s 29, I think, but I had him when he was younger when he was a kid. What he was doing then ... wow!
“He’s starting to get somewhere back towards that level now, but he’s never been one ounce of trouble.”
McClaren has also defended striker Papiss Demba Cisse.
He said: “Papiss? Never been one ounce of trouble. Never been. There was all this stuff about them being late and everything, not at all.
“We have no real issues. We’ve just got a little bit of hangover from the past.”