STEVE McClaren revealed last night how he has copied Sir Alex Ferguson's blueprint for success by helping Middlesbrough laugh their way to the top.

Behind Ferguson's dour exterior, McClaren insists, lurks a "wicked" sense of humour that keeps a smile on the face of Manchester United's football.

Having worked with Ferguson and the ever-jovial Jim Smith, the Middlesbrough manager realises the importance of running a happy ship as well as a winning one.

He is now reaping the benefits of such an approach, with coach Steve Harrison the man credited by McClaren as being largely responsible for generating an atmosphere that has seen the grimaces of recent years replaced by grins.

McClaren, whose side visit Charlton Athletic tomorrow, said: "The camaraderie at Manchester United was tremendous.

"The banter builds the togetherness and team spirit that all great sides have, and we're trying to emulate that here.

"The most important thing at a football club is team spirit and the respect that everyone has for each other.

"Sir Alex Ferguson has got a wicked sense of humour, which is something you've got to have if you're going to do well in football.

"Sir Alex doesn't portray that image in public, but believe me, behind the scenes a sense of humour is his No 1 priority.

"I was fortunate to be with Jim Smith, who also has a very good sense of humour, and Steve Harrison is a funny guy, too.

"One of the reasons I brought in Steve was that not only is he a great coach, but he's also one of the best at creating a good atmosphere in the dressing room.

"You need someone at your club that's good at that and Steve provides it. With him, I've got the best of both worlds.

"You'll see practical jokes and people generally trying to enjoy themselves at any football club.

"Clearly, it's better to work in an environment that's always smiling than one where everyone's miserable.

"But it takes a special person to create that atmosphere within a dressing room. Steve is one of the best at that; he's a great link between myself and the players.

"The players I've brought in have also helped. The day we signed Geremi was a very long day because we had to sort out all the legalities.

"But he never stopped smiling all the way through the day and he's done that ever since he joined.

"He's brought Joseph Job out of his shell, and George Boateng is another one who is always happy."

McClaren is well aware third-placed Middlesbrough could have the smile wiped off their face in their next five Premiership matches as they enter a defining phase in their season.

After facing Charlton, Boro host Leeds United and Liverpool, and visit Newcastle United and Chelsea.

It is a testing run of fixtures and McClaren admits his side, who have won their last three league games, will have a clear idea of their capabilities this season in a month's time.

McClaren, who ruled out a move for Arsenal striker Francis Jeffers, said: "Our next five weeks will determine how far we've come and how far we can go.

"People have to be sensible. We know there are bigger tests ahead and consistency is the name of the game.

"We're playing well at the moment, but the reason teams like Arsenal and Manchester United always finish high is because they perform at a certain level week in, week out."

Read more about Middlesbrough here.