Shouldering the hopes of a war-torn Northern Ireland, the Commonwealth champion struck Olympic gold with a world record-breaking performance that included four personal bests. Holding off German rivals Heide Rosendahl and Burglinde Pollak, the margin of victory was just ten points.

Olympic Games, Munich, September 2-3, 1972 – pentathlon, gold. 4801 points (WR)

I went to the Tokyo Olympics in 1964. Going to Japan, that was major. I ended up fourth, while Mary Rand came second, and it was the experience that showed me I could compete at that level.

We didn't have a pentathlon in the Commonwealth Games at that stage – it didn't come until 1970 – but I loved the travel, the friendship and the experience of competing. In my mind, I wasn't ever going to be a champion. I had to be convinced that I could be good enough.

I got two Commonwealth golds in Edinburgh in 1970 [pentathlon and shot put]. I was always afraid that people wouldn't like me if I was too successful, which is a stupid thing to say, but I was living in Belfast on my own. My family had all gone. My brother had emigrated to Australia, my father had remarried after my mum died and gone back to England. I was a Lone Ranger, but I think I wanted to prove something.

A year to the day from competing in Munich, we went to Crystal Palace. My coach Buster McShane had a video camera and he filmed all the people doing the Fosbury Flop. When they'd all finished, he went down and said: “Would you leave the equipment out so Mary can have a go?” He filmed me doing the high jump because we didn't have high jump beds in Belfast. And I jumped higher than I'd ever jumped before.

I applied for a Churchill Fellowship, which was going to allow me to train in America in the sunshine without having to work full-time as a teacher. I stayed with Bill Pearl, who was Mr Universe five times. He had a gym and used to get up at four o'clock in the morning, and do weight sessions. People would come from all over California to take the weights off him, such was the privilege. 

He lifted weights that nobody else had, so I was lifting heavy weights too. One of the exercises I did was the vertical jump, so that I could get over the high jump bar. I was like a donkey in the high jump before that. It worked for me because I had strong legs, and I held the world record for the best vertical jump at one stage.

Before Munich, a few journalists took me for dinner. I'm ashamed to say this, but I was smoking and drinking gin and tonics about a week before I went to the Games. They said: “How do you think you're going to do?” And I said: “I’m bringing back the gold.” 

When the first day of the pentathlon ended, it was going the way I wanted but I still had the high jump, and then I had Heide in the long jump and 200m so I couldn't be complacent at all. I used to do a pentathlon in one day and love it, but to split it up into three sessions was awful.

I went back to the Village, had something to eat and a little rest, then came back out again. You get bored hanging around. I knocked the high jump bar off twice at five-foot-seven (1.71m), and my coach told me to get running, so I did. I went up and up and up and over. How I did it, I'll never know.

I feared Burglinde more than Heide, but Heide jumped out of her skin in the long jump. We came off that, then had to come back again at night to do the 200m.

I got it wrong. I thought they would take the highest-placed competitors first, and we would be in the first heat. Of course it was the other way round. I was warmed up and ready to go and Buster said: “Just go and lie down on the high jump bed,” which I did, and relaxed. Then they called us for the 200m, and he said: “You have to run faster than you've ever run before. Use your arms. Your legs only go as fast as your arms.”

I knew I could only do what I could do. Heide kept going away from me. I didn't know that I had won until she came up and congratulated me because it took so long for them to add the scores up. She was supposed to be the star of Munich and it ended up as such a small margin between us – just ten points.

I didn't know her terribly well, but she'd also had a threat to her life as a Jewish lady. She’d had to move out of the Village. She was so sweet and she offered me one of her cigarettes as we were celebrating.

The prime minister, Ted Heath, came down and congratulated me. One of his private secretaries said to me: “Will you come for lunch tomorrow?” I said: “May I bring my coach, because it's due to him that I have won?” He said: “No, he wouldn't be invited because he's not part of the British Olympic team.” So I told them I wouldn't be going either.

We did go out but Buster said: “I need to talk to you…” There had been a phone call to the BBC to say that, if I came home, I'd be shot, and my flat would be bombed. They told my father. He wanted to take me home with him to Australia [where he lived by then] and I said: “Absolutely not. I'm going home to Belfast.’”

I wanted to come home and share my medal. When I got to Belfast, they wouldn't let people into the airport because of The Troubles. There was barbed wire and they were hanging baskets of flowers over it. They put “Welcome Home Mary” on all the lamp posts, but I never saw any of it because they took me on a different route.

I was in a gold Rolls Royce and they were playing “Congratulations”. I have the happiest memories of that day. They took me down Royal Avenue on the back of a lorry. People still say to me: “I was there that day you came home.”

We were going through such troubles in Northern Ireland. It was a terrible time, with so many people dying. I wanted to bring some good news back, but I didn't know it was going to be as good as it was. And it changed my life forever.

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