WHEN Sir Bobby Robson steps back into the capacious environs of the Nou Camp this evening, he could be forgiven for wondering what might have been had he allowed his heart to rule his head nigh on six years ago.

Robson, plain old Bobby in those days, had been manager of Barcelona for roughly only half a season when he received a phone call that presented him with the most agonising decision of his professional life.

It was January 1997, Kevin Keegan had provoked near-hysteria in Newcastle with his sensational resignation, and then-chairman Sir John Hall was bound for Spain on a mission to persuade Robson to become the next managerial incumbent at St. James' Park.

For a Magpie fanatic, born in Sacriston and raised in nearby Langley Park, it was the chance to realise a boyhood dream.

But Robson is a man of principle, and though the pull of Tyneside was great, he resisted temptation and agreed to honour his Nou Camp contract at the behest of then-president Josep Luis Nunez.

The former England boss did so despite the first rumblings of insurrection among the Barca faithful. The dreaded white handkerchiefs, a symbol of the fans' displeasure, were given an airing and the Catalan catcalls of many were for Robson's head.

Yet, before too long, those same supporters were celebrating silverware as a defiant Robson led Barca to the European Cup Winners' Cup and Spanish Cup.

It is with a heavy irony, then, that tonight's Champions League game should pit Robson against Louis van Gaal, the coach who succeeded him at Barca - especially as the Dutchman only began his second spell in charge in the summer.

Robson's fatal failure with Barca was losing the domestic title race to deadly rivals Real Madrid.

For that he was unceremoniously bundled upstairs after just one season in command and forced to accept the sop of a supposedly high-profile global scouting role.

At the time, Robson maintained a dignified silence on the matter, though his ego was understandably badly bruised.

His frustration was exacerbated by the fact that, just months earlier, he had turned down the job he always wanted.

And his regret deepened when he learned that Nunez had been plotting all along to replace him with van Gaal.

So when the offer came Robson's way again in September 1999 following Ruud Gullit's departure from Newcastle, he hadn't a moment's hesitation in saying 'yes'.

Who knows? Had Robson answered in the affirmative the first time, it might have been he - rather than Kenny Dalglish - who led Newcastle to that treasured 3-2 Champions League triumph over Barca at St. James' five years ago, when Faustino Asprilla fired a remarkable hat-trick.

But Robson, who beat cancer seven years ago, refuses to view himself as a victim of the vagaries of fate.

"If I'd known what was going to happen at Barca, I would have gone to Newcastle,'' admitted Robson, who had guided the Catalan giants into the Champions League.

"We'd had a remarkable year, I nearly did a quadruple. I was only two points off winning the league, we won the European Cup Winners' Cup, the Spanish Cup, the Spanish Super Cup, and scored over 100 goals - and I still got bombed!

"But I have no bitterness - it was just bizarre. It was still a great time in my life. I had two wonderful years there and I enjoyed it very much.

"I made it easy for them by moving aside when they appointed Louis van Gaal. I didn't have an argument with him; it wasn't his fault and we're good friends.

"But I stayed away from the ground, kept a low profile and killed myself really. It was a hard year, but I used it as a sabbatical.

"I went to watch football in places like Brazil and Argentina. Barcelona are probably still benefiting now from some of the work I did as a scout.

"When I eventually went I was sorry to leave a city I loved. I had to make a major decision because I was offered the chance to stay on, but not in the capacity I wanted.

"If I'd been allowed to stay in charge, I think Barcelona would have seen the best of me.''

Robson, however, insists he isn't looking to prove a point as he prepares to make a sentimental journey to his old stamping ground, where he is certain to be afforded an affectionate reception.

"I don't really want to show them anything, because they knew what I could do,'' said Robson. "I got there in the first place because of my record and reputation - I followed Johann Cruyff.

"I'm just proud to be leading Newcastle there, because I never thought it would happen.

"It's going to be a white-hot European night. It's a majestic stadium when it's full and vibrant with 100,000. It's compelling - it really is a magical place.

"There's no better stage, honestly. Playing for England and being in charge of your country at Wembley was something akin to that.

"But that only happened three or four times a year, whereas being at Barcelona was every two weeks. It has an aura and it's colossal.''

And you can be sure that Sir Bobby is still a colossal figure over here.

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