'Big Jock couldn't believe it. "Do you really want to go to that elephant's graveyard?" he asked me.
'But Haldane Y Stewart could sell sand to the Arabs and he'd convinced me I was the best player since Pele.'
Stewart may not actually have believed that much. Within two seasons, however, there were plenty around Greenock who did. Initially, the reception and first impressions were underwhelming. A leaking gas fire created the impression of a gas chamber in the old Cappielow main stand when the new signing arrived on the morning of his debut against a Clydebank side featuring the late Davie Cooper. An air of decay hung over Cappielow and circulated the corridors.
'I remember meeting my great boyhood hero, the former Motherwell striker John Goldthorpe, as I walked in.
' "Andy, what you doing down here?" he asked me.
' "I'm playing against Clydebank tonight, John," I replied.
' "You're whit?" he asked me. "What? Are you down on loan?"
' "Naw," I said, "I signed for Morton this afternoon."
' "What the f*** did you sign down here for?" he asked me. That wasn't the best of starts.
'But the real culture shock arrived on the Saturday, when we went to Love Street to play St Mirren, our greatest rivals. We lost 5-1 to a team managed by a certain Alex Ferguson. That Saturday night, I drove home saying to myself, You'd better get your finger out; you don't want to be hanging about here too blinkin' long.'
Yet when the goals started flowing with a double against Montrose the following Wednesday, including a trademark free-kick, Ritchie settled. So well, indeed, that within weeks Celtic - unbeknown to the great man himself - tried to take him back for £170,000.
'Had I known at the time, I would have created merry hell to secure my return to full-time football. It was only many years after I had finished as a football player that I even learned of the bid from Sean Fallon, Jock's old assistant.
'As part of the deal, Morton would be duty bound to clarify that I had only ever been on loan. It's difficult to explain in words how I felt about it years later. I just wish to Christ I had known at the time.
'I quickly realised at Morton that I had never really wanted to leave Celtic. But Brings had gone so far, relations had soured so badly, that I had to. I was putting pressure on myself to succeed and I had to get away, to reinvent myself.'
To a large extent, he succeeded brilliantly. After scoring the goals which took Morton to the Premier League in a season-and-a-half, Ritchie became that rarest of entities: a Player of the Year plying his trade outwith the Old Firm.
When he earned his accolade from the Scottish Football Writers' Association in the Albany Hotel, Glasgow on an April night in 1979, he was just 22. The pride he took from having his father and grandfather in the grand room that evening was palpable. By his own admission, however, the award prompted a downward spiral rather than an unstoppable ascent.
In the days before footballers enjoyed rock star status, the celebrity that followed was difficult for a young working-class man with an attitude and a healthy slice of self-conceit to absorb.
'Things began to change after that,' he recalls. 'I parked my car outside a primary school in Greenock one day and young boys were playing football in the playground. One of the lads scored a screamer past the obligatory fat kid in goals. And as I turned the lock in my car door, I heard the shout, "And Ritchie scores!" I thought he was taking the piss. He wasn't, the kid hadn't even seen me. But at that time my reputation was growing all over the place. I was being recognised everywhere I went, from Laurencekirk to Lochee.'
What had also changed was Ritchie's attitude. The good habits bred at Celtic had flown out of the window to be replaced by heavy drinking, major gambling and a 40-a-day nicotine addiction. By his own admission, he played many of his best - and worst - games nursing a hangover. Friday night sessions in the Windmill Tavern in Lanarkshire would be followed on Saturday morning by a panicked search for the family car, a missing wallet and a phone call to an obliging teammate to get him to Greenock for the prematch meal, where manager Benny Rooney would be pacing around a hotel foyer checking his watch.
'I always remember Johnny Goldthorpe driving me to training at Morton one evening in our promotion season in 1978.
'Johnny was 32, had been a good pro and knew a thing or two. I had always looked up to him until the day he turned to me in the car and said, "You'll not last until you're 27 in this game."
'I was angry, furious in fact. I wasn't having that, not even from Johnny Goldthorpe. I was only in my early twenties at that time and I was flying. I was scoring goals, winning rave write-ups and was the best player in the country. What did this old fella know? Well, one thing he did know was the smell of drink - and I was in that car passenger seat steaming drunk. I'd been drinking all afternoon, and some of the morning as well. And that wasn't especially unusual for me. I'd still be stinking of drink when I played games. And somehow I was still scoring goals.
' "I'll do whatever the f*** I want," summed up my attitude best.
'Big Jock Stein had told me towards the end of my time at Parkhead - because I had begun to develop an opinion - that the best thing I could do was take the cotton wool out of my ears and shove it in my f****** mouth.
'Don't get me wrong, I enjoyed every minute of all that. I didn't do it to blot out any pain or any crap like that. But I saw no need to change. I had been boozing, gambling and doing whatever and we had still gone to the top of the league.'
Morton finished seventh in the Premier League that season, after leading before Christmas. Part-time football remained a constant despite promises from the chairman, Hal Stewart, to go full-time. To the more ambitious members of the playing staff, it was a betrayal.
Desperate to play for Scotland and increase basic earnings of £50 a week bolstered by a new contract and an afternoon job as a Morton Lottery Ticket salesman, however, Ritchie wanted out. With his gambling now out of control, he needed out.