He became a teacher instead and did pretty well because at 27 he was head of Pentrecelyn School, near Ruthun in north Wales. About the same time, he started taking singing lessons again - there wasn't the time for rugby, now that he had responsibilities, and he fancied a change. In 1996, after two years' study and at his first attempt, he won the Blue Ribbon for singing at the Royal National Eisteddfod in Llandeilo. Life has never been the same.
"People started approaching me and saying I should become professional," he says, "and I went to sing for Carlo Rizzi at Welsh National Opera. He said it would be a sin if I didn't train." A year later he was studying at the Guildhall School of Music, and now he is preparing to sing Edmondo in Puccini's Manon Lescaut at Glyndbourne, with the prospect of an English National Opera contract starting in August. He will be returning to the Eisteddfod in Llanelli next year as a celebrity guest.
As headteacher of a small school, Meirion taught everything and was keen to encourage children to take up music, especially singing. Under his guidance, Pentrecelyn School choir won prizes at the National Eisteddfod despite having only 65 pupils on roll. Most of the junior competitions at this major annual celebration of Welsh culture are for under 15s, but there is plenty of scope for primary children too.
The location of the Eistedfod alternates between north and south. This year, from August 2 to 6, all of Wales will be flocking to Anglesey, where the country schools are often very small. Four of them will be needed to supply the dancers for the main ceremonies, the Crowning and Chairing of Bards.
Lynne Jones, of Pentraeth School, is co-ordinating the 24 children (including four reserves) aged eight and nine, teaching them the steps which have remained substantially unchanged for decades. They have been rehearsing regularly since Christmas. Parents have helped sew the costumes according to the traditional pattern - green, short-skirted, round-necked dresses - and they are able to make another important contribution too: some of them have farms and wild flowers are essential for the ceremonies.
"We'll be up at five in the morning on the days when the children are performing," Lynne Jones says. "We have to collect particular fresh wild flowers - honeysuckle, dog daisies, poppies and gyp - and some ivy. It's very hard to find enough. Then we set to work and it takes hours to make the garlands, posies and sashes."
The music for the two major ceremonies also follows a time-honoured pattern. "We do have some choice," she says. "We are going to have two violins to accompany the harp. Other people sometimes have recorders."
The Crowning and Chairing, surrounded by the ceremonial of the Gorsedd of Bards - the exclusive group of poets and musicians permitted to wear druidical robes - are solemn occasions, an indication of the respect for poetry in Wales.
But there is plenty of fun to be had too, including a Rock Tent where alcohol will be on sale. The 19th century Nonconformist ethos still looms over the main Pavilion, but the young flock to camp out, compete seriously, then go to gigs in the evenings.
Bryn Terfel is the big star this year. He will be singing a medley of songs on Thursday August 5 and Faure's Requiem on August 6.
Supporting him on Thursday evening will be teenagers from Ysgol Glanaethwy, stalwarts of the Schools Proms, famous for the high standard of their Welsh-language music theatre.
The language on the Maes is Welsh, but everyone speaks English and there is instantaneous translation available in the main pavilion.
For information: 01222 763777