Former footballers are fascinating people to catch up with.

Some are hard men, either vain or arrogant, who are rolling in money. Others - quite a few, actually - are modest and unassuming, akin to a very likeable neighbour over the fence. A man such as Tom McAdam.

The former Celtic defender of the late 1970s and early 1980s is now 59, and drives a delivery van around Glasgow until all hours of the night.

Tom had been living quietly, but emerged from the shadows three weeks ago due to the sudden death of his brother, the former Rangers striker Colin McAdam, at the age of just 61.

So there was Tom, the once handsome, flaxen-haired figure of his playing days, at his brother's funeral. A throng of 500 turned up at Clydebank Crematorium. "It was unbelievable," Tom says. "It was amazing to see that so many people had respected Colin."

They had grown up pretty close, always playing football together, with Colin, the older by two years, being the harder one. Someone once perceptively noted that, while Tom was fair and even slightly angelic to behold, Colin on the other had was a bit ungainly, with a squashed boxer's nose and a rasp of darker, unkempt hair.

"Colin was the clever one of the two of us: he got eight O levels and five highers," said Tom. "But he was also a bit of a hard man, he could look after himself. Quite often in games when we were young, if someone landed one on me, Colin would say: 'Don't worry, I'll get him.' Maybe he was just joking but he was a hard opponent.

"It was actually Colin who got me into professional football. He was at Dumbarton in 1970 and said to the club, 'why don't you go and look at my wee brother . . . he gets lots of goals.' The next Saturday a scout came to watch me, and in that one game I scored eight goals for Weir's Pumps in a 12-1 win against a bottom of the league side. It sounds amazing but it's the truth, and Dumbarton signed me on the spot. I was just 15."

It was many years later, though, when fate would bring the brothers face to face in the heat of an Old Firm derby. In the early 1980s, fans were fascinated by the jousts of the McAdams of Rangers and Celtic. Prior to that, though, Jock Stein had crucially intervened.

"I'd left Dumbarton [in 1975] to go to Dundee United, but I wasn't happy under Jim McLean," said Tom. "Wee Jim was doing my head in; he was a nutter. I was a striker back then and was scoring a few goals, but I wanted away. To be clear, I didn't hate Jim McLean at all. And he was a great manager, there is no argument. But he was doing my nerves in.

"One day he called me and said: 'There's a club in for you . . . are you interested?' I told him I was and he said, 'Right, it's Celtic, so get down to Glasgow.' I couldn't get myself down quickly enough to speak to Mr Stein, who came and picked me up at Queen Street station. As I was leaving Wee Jim told me: 'You'll be getting no money from us when you go.' That was typical of him. I didn't care. I wanted away. And I was going to a huge club like Celtic."

A story was unfolding which would bring Tom and Colin face to face in Glasgow. In truth, Tom did not settle at Celtic initially, but injuries then forced new manager Billy McNeill's hand in the spring of 1979 and, on a momentous night at Celtic Park in May of that year, McNeill asked McAdam to fill in at centre-back for a title-decider against Rangers; a game 10-man Celtic won 4-2.

That night the home fans discovered that, out of nowhere, they had a new central defender. "I'd spent a lot of time on the bench, but then came that famous night in 1979," he says. "I was a stop-gap that night but my Celtic career took off after that. I had pretty much six very happy seasons there after that.

"It was Big Billy who asked me to play centre-half. I'd always been a striker but when I went back into defence I found I really enjoyed it. And I was always decent in the air. Funnily enough, Colin went the opposite way. He started out as a defender - he even played right-back when we were at Dumbarton together - but then moved up front in his career. It's a strange one, that."

In the years that followed, with Colin now at Rangers, the brothers faced each other in several Old Firm derbies between 1980 and 1982. There was not always an outpouring of familial love.

"We got a lot of attention when Colin went to Rangers from Partick Thistle [in 1980] and I was at Celtic. We faced each other quite a few times in games and quite often there would be dirty tricks, elbows and such.

"We played one game at Parkhead when I elbowed him as a corner was coming over and, about 10 minutes later, up at the other end, he put a gash in my leg in retaliation when I was trying to shoot. I needed to get stitches put in it at half-time. I remember Sportscene on the BBC made a thing of it later that night. They played Neil Sedaka's Little Brother over an edit of me and big Colin going at it. They were great times. We always respected one another and shook hands at the end. But we had battles."

Tom left Celtic in 1986 for Motherwell. Colin had already left Rangers after four years at Ibrox. "I left Celtic when I was 32 and feeling as fit as a fiddle," says Tom. "Fair enough, Davie Hay came in and wanted to make changes. But 32 today is nothing for a central defender."

Recent weeks, and the sadness of his brother's passing, have brought back memories of these more innocent days in Scottish football. Plus this horrendous thought: time is marching on for all of us, once the young men.

"It was shocking when Colin died, totally shocking," says Tom. "He had suffered a mild heart attack and my wife and I went up to see him at the hospital. He was sitting up, laughing and joking, and we left and went home.

"But a couple of hours later the hospital phoned and said he'd had a setback, a brain haemorrhage, and was on a ventilator. He died shortly afterwards. The doctor said he had suffered a terrible reaction to being given warfarin. But being given it, I was told, was a routine procedure for some people who had suffered heart-attacks.

"As I say, Colin's funeral was amazing. Around 500 people turned out, it was a terrific show of respect. We had some great times, I'm happy to say."