Former England rugby international Josh Lewsey and Saracens star Don Barrell have paid tribute to their former PE teacher, who has started retirement after 100 terms at a Watford secondary school.

John Williams, 58, joined Watford Grammar School for Boys in 1977 from Christ College, Brecon, where he was capped for Welsh Schools in rugby and hockey, and Cardiff College of Education.

Then as Director of Sport, he has overseen an expansion of sport at the school, and led teams on tours to Australia, South Africa, New Zealand and Canada.

He has served under five headmasters and taught more than 6,000 pupils.

Josh and Don were due to lead opposing teams in a testimonial match at Fullerians' RFC, in Coningsby Drive, yesterday (Friday) but the match was called off due to the frozen pitch and inclement conditions.

World Cup winner Josh started playing rugby aged four but said John helped him choose the sport over football.

He said: “I came to Watford and concentrated on rugby. John was sports master and I remember this red-haired, fiery Welsh PE teacher. If things weren't done to his level, he wouldn't mince his words.

“The old faces here today show what sort of affection he has in people's hearts and what people think of him.”

Don, who went to Watford Boys' from 1997 to 2004, said one of his career highlights was when his side were the heavy underdogs in a match against Royal Grammar School High Wycombe, but won 14-11, in December 2001.

“We weren't meant to be in their league,” said Don.

“John took me under his wing from the County under-14s up to Sixth Form and I still use him as a sounding board today.

“He's honest but always in a nice way. He's quite humourous and has a very good manner. People want to work for him. It will be a sad loss to Watford.”

Martin Post, Boys' headteacher, said John was “both unique and typical of the kind of staff we get at Watford Boys'”.

He said: “He's given 100 terms of service to the school. He's probably worked every single Saturday in that time as well as doing the day job and he fully deserves his retirement.

“It will be hard to match his complete obsession for rugby at the school. He regularly is down here on a Friday night and making sure the match balls are clean for a Saturday. You cannot buy that sort of commitment.”

Father-of-two John, who lives with his wife Liz in Cassiobury Drive, said he had no immediate plans for retirement but would continue to follow the school's sporting achievements.

“It's been such a hectic end to the term I haven't had time to think about it,” he said. “It will hit me when they go back in January and next September with the rugby team. It's been quite emotional and boys have been giving me their best wishes.

“One of the things I am most proud of is giving boys a chance to participate in a variety of sports. I get as much enjoyment teaching the Under-12s D-team as I do with my first team.”

Looking back on his teaching career, John said bringing future international players through the ranks was an “obvious highlight”.

“The pinnacle has to be Josh lifting the World Cup,” he said. “When the commentator watching the match said it was a proud day for Watford Grammar School for Boys, it was really fantastic.

“This is what the school is about. It really has sport as a key part of the school.”