In the space of one week, Michael Essien has shown himself to be a brute of a footballer, one you would shield from the eyes of children . . . and also a player of such breathtaking pace, grace and power that he might make the difference to Chelsea going all the way in Europe this season. One cannot excuse the other. We live in weird times when referee Rob Styles last Saturday saw Essien stamp his foot over the ball, his full set of studs coming down onto the legs of Bolton?s grounded Tal Ben Haim, and offered up only a yellow card as punishment.

Manager Jose Mourinho, not always the friend of match officials, had nothing to say. Fifa chose this incident to stamp its own authority over the Football Association, stating that video horrors must not affect decisions even when the referee himself admits the playback showed that the yellow card should have been a red.

No going back, then. We must remember that. In the meantime, Essien made us marvel at his performance in the Champions League on Wednesday when he, more than any man, took the game away from Real Betis of Seville.

There was force, mostly legitimately applied. There was athleticism and energy to amaze. There was an eye for the pass and a cunning to deceive on the run that set up two of Chelsea?s four goals.

Above all, after just 10 starts in Chelsea blue, there was the amalgamation of what Essien can do in a midfield that combines the major contributions of Frank Lampard and Claude Makelele.

There are better individuals in football but is there a more authoritative unit? For 24 minutes Betis?s fluent one-touch passing, with Joaquin?s sorcery on the right, threatened to stretch and surprise Chelsea.

But then a stray ball from Alberto Rivera was seized upon by Essien, who surged 20 yards. With everybody anticipating a pass to Shaun Wright-Phillips on the right, he deceived them by guiding the ball inside to Didier Drogba, who tucked the goal away.

Later, before creating another goal for Joe Cole, Essien was blameless when Miguel Angel Lozano tried to tangle with him and damaged a cruciate ligament in the attempt. There were many times when Betis players were overpowered by him but only once, in a dangerous two-footed lunge, did he foul unacceptably.

Once is more than enough, yet Terje Hauge, the otherwise excellent Norwegian referee, showed no card. One suspects that, while Essien gets away with it, Mourinho will show no inclination to curb the nasty edge to his player any more than Manchester United?s Sir Alex Ferguson did in a decade with Roy Keane or Arsenal?s Ars?ne Wenger did with Patrick Vieira.

Modern managers think intimidation is part and parcel of the make-up of the warrior players who ?stick their foot in?. It will be a pity if we have to wait for braver referees to curb the aggression of such a potentially fine player.

Essien was born and raised in Accra. He was a boy obsessed with the ball, a youth known to many a talent scout because of what he did for Ghana at African and world Under-17 tournaments.

At 22, he stands a shade under 6ft and weighs just over 12st. Yet he comes with such strength and stamina that French colleagues at Olympique Lyonnais dubbed him The Bison. Hold on and you?ll get trampled in his wake, was the warning.

Stamford Bridge teammate Joe Cole says: ?He?s just the best football athlete. He?s got everything ? strength, pace, he can run all day and he?s clever with the ball. I have not seen anyone to match him.?

Coming from Cole, who has played with Steven Gerrard and Lampard and against Keane and Vieira, that says a lot. Mourinho endorses it, adding that Essien is a multi-functional footballer who has played left- and right-back, central defence and holding or attacking midfield.

Chelsea pursued him on the rebound after being rebuffed by Gerrard and even after the long summer bartering during which Lyon drove up the price to ?26m. He speaks English and lives and sleeps (apparently up to 13 hours a day) for the game. He listens to his mother and his agent, and wanted Chelsea so badly that he went on strike to force Lyon to sell him. For a drop in the ocean of Roman Abramovich?s wealth, Essien might turn out to be great value. Many knew he was a good prospect but few could have known just how good until he took Wednesday?s game by the scruff of the neck.

Makelele is almost a decade ahead of Essien, yet he deferred to the younger African with alacrity. Lampard is at the top of his game, yet he was less the marauder than Essien. Mourinho enthused: ?Michael won every challenge in midfield. He gave a different pace to the game. He was too strong for them.? In the Chelsea side that has scored 13 goals, conceding two, in the past three matches, the midfield has dominated.

Abramovich states in the foreword to the book Chelsea FC ? The Official Biography, published tomorrow, that his aim for the club is to get beyond the semi-finals, where Chelsea have fallen in the past two Champions Leagues, and to build a world football power that will last 100 years.

Mourinho reckons he might be around for five of those. Essien could potentially be there longer, especially if he endures the way his countryman Marcel Desailly did. And while he is at Stamford Bridge, he cannot be anywhere else.

This is to the chagrin of Wenger, who lost Vieira to Juventus, and painful to Ferguson, who is struggling to find Keane?s successor. Not for the first time, Chelsea, aided by former Old Trafford colleague Peter Kenyon, moved in and outbid Sir Alex on what he coveted but could not afford.

It gets even worse for United. Essien was theirs for the signing at 17. He was the hottest prospect of a fine Ghanaian youth team and Ferguson had him on trial at the Carrington training ground.

Essien wanted to join, Ferguson saw enough to make the move but Kenyon, then at United, could not close a deal. Essien had no work permit to come to England so United proposed to farm him out to Royal Antwerp, the club?s Belgian ?nursery?. Essien?s agent said, ?No go?, and Mum told him to listen to his agent. He went to Bastia and moved on to Lyon, who ended up almost quadrupling their investment after just two seasons.

His personal fortunes have risen to the ?5m-a-year bracket. His adaptability seems to take most of what is happening to him in his stride. Whether he knows how to cope with the downswings or the inevitable uncompromising approach that Chelsea?s forward momentum demands, only time will tell.

Whether Mourinho has the patience or is granted the time to teach him to keep his boots on the ground, in every sense, may hold the key. For now, it is fast forward into Europe rather than playback on the incriminating taped evidence that he possesses a nasty streak.

Uefa?s statistics suggest Essien is more than capable of playing within the rules. His record shows he has been more sinned against than sinning. He has been whistled for eight fouls and suffered 10 in three Champions League matches with Chelsea. And there is a dimension yet to come, judging by the five goals he scored last season in 10 Champions League appearances for Lyon.

Somewhat ahead of his years, he has a pivotal role to play in taking Chelsea that one step further to European glory and then his beloved Ghana to its first World Cup finals.