Terry Griffiths, who has died aged 77 after suffering from dementia, became world snooker champion at his first attempt in 1979, just as the sport was transforming itself from a low-profile activity into a television attraction enjoyed by millions. A rookie pro from Llanelli who was new to TV audiences, he beat four leading players of the day, Perrie Mans, Alex Higgins, Eddie Charlton and Dennis Taylor, to reach the summit of the sport.

Griffiths had only turned professional the previous year, having realised that the game was beginning to provide more opportunities for fame and fortune or, at the least, a chance to earn a congenial living. Although the tournament circuit was not yet fully formed and it was far from easy, at that stage, to obtain the two club exhibition bookings a week at £70 a night that were needed to stay on an even financial keel, he had decided to take the plunge.

It was a bold move given Griffiths’s responsibilities towards his wife, Annette, and their two young sons, Wayne and Darren, and he must have soon had some doubts when his first professional match, in late 1978 against Rex Williams in the UK Championship qualifying competition, provided an agonising setback, as an 8-2 lead turned into a 9-8 defeat.

He travelled to the World Snooker Championship qualifying heats a few months later with no higher ambition than to earn enough money to pay off his car loan.

However, after qualifying for the main competition at the Crucible theatre in Sheffield he had a relatively comfortable 13-8 win on his debut against Mans, the 1978 runner-up, and then came through two contrasting epics. First he met the brilliance of Higgins with deadly counter punching, clearing the table to snatch several frames on pink or black from 60-odd behind and going through 13-12. Then, in a semi-final against the dogged, resilient Charlton, he became embroiled in a war of attrition that required a final session of five and a half hours and a 1.40am finish before he was able to prevail 19-17.

In the final against Taylor, Griffiths started the last day only 17-16 ahead but pulled away without further loss to win 24-16 and pocket the first prize of £10,000. The veteran former world champion Fred Davis declared that, in view of Griffiths’s lack of experience of long matches, “Terry winning this has been the greatest achievement the game has ever known.”

Griffiths was born in Llanelli, south Wales, to Martin, a steelworker, and Ivy (nee Howells). Expelled from Llanelli grammar school for truancy and then transferred to a secondary modern, he left at 15 to work variously as a blacksmith’s apprentice, miner, bus conductor, postman and insurance agent.

Although he played snooker to a good standard in his spare time, it was not until he was 24, unthinkably late by today’s standards, that he made his first century break, and his first major honour – the Welsh amateur title in 1975 – did not arrive until he was in his late 20s. After that, however, his star rose quickly, and he also won the English Amateur Championship in 1976 and 1977 – the event then being open to Welsh players.

After winning the 1979 World Snooker Championship, Griffiths won the Masters in early 1980 by beating Higgins 9-5 and then followed up with the first of three consecutive Irish Masters titles (1980-82). But his 1980 world title defence did not survive his first match, as Steve Davis, then emerging as the dominant player of the 1980s, went 7-0 up and beat him 13-10.

After two more trouncings at the hands of Davis in the UK Championship, 9-0 in their 1980 semi-final and 16-3 in the 1981 final, Griffiths became concerned that the younger man was opening up a gap that might never be closed. As a result he began to look closely at his technique by consulting the father of modern snooker coaching, Frank Callan, whose precepts became key to his own coaching career later on.

In 1982 Griffiths completed the third leg of what is now known as snooker’s triple crown – the world, UK and Masters titles – by beating Higgins 16-15 in the UK final after scoring a rare win over Davis, 9-6, in the quarters. Later that season he and Davis contested four consecutive finals, Griffiths winning the first (the Lada Classic) and the fourth (the Irish Masters), while Davis took the Masters and the Yamaha International.

They were widely expected to meet in the Crucible final that year, but both lost in the first round, Davis to Tony Knowles, Griffiths to Willie Thorne, and Higgins won the title.

After 1982 Griffiths never won another major title, although he consistently reached the late stages of tournaments and retained his place in snooker’s top 16 for 17 years until 1996 – with a peak world ranking of No 3. Over that period he contributed fully to some memorable matches, labouring until 3.51am for a win against Mark Wildman at the World Snooker Championship in 1983, for instance, only to lose his second round match to Cliff Thorburn 13-12.

Griffiths retired from the tour in 1996, full of enthusiasm for his new role as director of coaching at the World Professional Billiards and Snooker Association. But he resigned in 1998 with £50,000 still left on his contract, describing it as it then was as “a hopeless set up … nothing constructive, just going round in circles”.

In 1987 he opened a club in Llanelli, the Terry Griffiths Matchroom, and moved into private practice, notably as house coach to a group of players, headed by Stephen Hendry, who were managed by Ian Doyle.

Quiet, modest, extremely popular in all sectors of the game, Griffiths was made OBE in 2007 and remained in demand for many years, not only for his knowledge of technique and shot selection, but for his deep understanding of the psychology of matchplay.

He is survived by Annette (nee Jones), whom he married in 1969, and his sons.

• Terrence Martin Griffiths, snooker player and coach, born 16 October 1947; died 1 December 2024

• Clive Everton died in September 2024