DEREK JOHNSTONE was in a pub in London with his new friends. Beguiled by the capital, and enjoying the best week of his life, he decided that he wanted to quit football.

No doubt about it, it was a momentous decision for an 18-year-old, one of the most talked-about young strikers of the time.

DJ hated life in the Glasgow goldfish bowl that came with being a Rangers hero, who had just added a European Cup Winners Cup medal to his collection.

He had money and knew he could get a job in London.

But his non-appearance in Glasgow that summer of 1972 did not go un-noticed. The papers were bleating DJ goes AWOL' - and Rangers themselves were far from happy.

Oblivious to the fuss, Derek had just ordered drinks in a Clapham pub when an unmistakeable voice behind him boomed: "And I'll have a half."

He glanced around to meet the gaze of big Jock Wallace, Rangers tough manager.

Derek froze. Was Wallace going to batter him right there and then?

Growled Jock: "You'll be on that plane first thing tomorrow morning and back at Ibrox, right, son?"All DJ could manage was: "Yes, boss."

The episode didn't end there, says Derek, now 53, on the eve of the Evening Times exclusive serialisation of his new autobiography, DJ: The Derek Johnstone Story.

"In his office the next day I apologised to him and said it wouldn't happen again. As I was turning towards the door, Jock gave me a full-blooded back-hander to the side of my head.

"Nowadays, he would be charged with assault, but that was the way the big man did things back then.

"I was in my teens, and it had all been too much too soon for me," he says of his amazing career. "I was just a stupid boy."

Then again, the Ibrox side could ill-afford to lose one of its finest strikers.

Dundee-born Derek, one of seven brothers, had been banging in the goals ever since he first got hooked on the game.

His potential was such that, at 12, top Scottish and English clubs pursued him.

At 14, only the terror he felt at leaving Dundee dissuaded him for signing for Arsenal.

In the end it was Rangers' chief scout Tommy Gray's persistence which paid off. 'I was a magnet for compromising situations' DEREK admits he was "too busy being Jack the Lad" to help raise his four children - they are Heather, Douglas, Judith and Donna - and that he became "a magnet for compromising situations".

He and his wife, Marion, broke up in 1999 after 21 years.

"There is no doubt it was mostly my fault," he reveals. "I was no angel and I deeply regret the hurt I caused."

Deek is now a grandad twice over. He has a grandson, Josh, four, thanks to his daughter, Donna, and his second grandchild is named Patience - for a very, very good reason.

"Judith, my youngest, was in labour for a long time and they were desperate for her to give birth herself," he says.

"But it was becoming more difficult and eventually she ran out of patience and decided to have a section.

"So she got that, and decided to call her wee girl Patience. It's a lovely name."

Tommy had often been in touch and the deal he struck with Derek's widowed mum - helped sway the decision.

"Celtic were going through their nine-in-a-row period, so it could have been even more tempting to go to them.

"But I have never, ever regretted signing for Rangers." says Derek.

Seven weeks after finishing school, he scored twice on his Rangers debut in a 5-0 win over Cowdenbeath at Ibrox in September 1970.

Five weeks later, he entered club folklore when a magnificent header at Hampden gave Rangers the League Cup - against Celtic.

It was Rangers' first trophy in four long years.

"Everyone goes on about that goal, which was fantastic - of course it was, in front of 106,000 people.

"But the first senior goal always means more to you. It was such a great feeling."

Two years later he was part of the team that battled its way to victory over Moscow Dynamo to give Rangers their first - and, so far, only - European silverware.

In all, DJ helped Rangers to two Trebles under Wallace, scoring 210 goals in 546 appearances.

He was worth his weight in gold.

But when Wallace's successor, John Greig, offloaded him in 1983, Derek wound up in London, at Chelsea, then a Second Division outfit.

They won promotion but Derek's role was marginal.

At one point they loaned him to Dundee United, his boyhood heroes, for a month.

In January 1985, he returned to Rangers, Wallace having replaced Greig.

But Jock made way for Graeme Souness and when Souey had no role for Derek, his time at Ibrox came to an end.

Looking back, he says he wouldn't change a thing.

"I had the chance to leave Rangers two or three times in my prime but decided not to. Rather than take the big bucks, I was happy at Ibrox.

"I loved the club. It grew into me and I didn't want to leave. Eventually, when I did leave for Chelsea, I was over the hill anyway.

"But I fulfilled everything I wanted to do."

His loyalty to Rangers was typical of the time - in contrast to some of today's highly-paid and much less talented players.

"It's different now when you're talking about the magnificent money that players get.

There was a lot of loyalty in the 70s. Most of the guys who played for the Old Firm were there for six, seven, eight years because they loved the club.

"Nowadays, because of the money situation, you're moving every two or three years.

"Players are a lot richer as well - I would imagine there are more millionaires now, even in the Scottish game, than there has ever been."

He doesn't share the view that the top wages are obscene.

"That's how it goes. The managers and chairmen can tell a player, No, you're not getting it'. But if you want quality you have to pay the money.

"In our day, it was an honour to play for the big teams. Now, it's just How much am I getting?'"

In his book, co-written with Evening Times sportswriter Darrell King, DJ is refreshingly frank about the highs and lows.

He discusses the break-up of his marriage, his disappointment at being left out of the Greatest Ever Rangers side, and his attitude towards Scotland boss Ally MacLeod, who cold-shouldered him during the World Cup in Argentina in 1978.

The book is serialised exclusively in the Evening Times with the first extract kicking off with the sensational revelation that Derek nearly signed for Celtic The father-of-four, who lives in Arrochar and is currently dating model June Lake, has long been one of the key names on Radio Clyde's Superscoreboard.

His health is good - though he needed an operation to correct a heart condition last year - and he is content with his lot.

"Workwise, I can't complain, and it's fantastic off the park for me as well.

"I don't think there's anything else I'd like to achieve."

However long he lives, he will remain a Rangers man - he's not exaggerating when he says that when he dies he'd like to be buried with a Rangers scarf.

He smiles as he remembers an incident from his brief spell with Dundee United.

"We were playing Rangers at Ibrox and I was warming up in the second half, but I sat back down again - in the Rangers dug-out. It was a natural thing after years with the club."

A growl reached him. "**** off," it said. "You don't play for us."

"That was another thick ear from Jock Wallace," says Derek. DJ: The Derek Johnstone Story is published on Thursday by B+W at £17.99

TOMORROW: Day 1 of our exclusive serialisation