Watch the Olympic triathlon closely and you might spot a very animated marshal on the route. Charles Lines is one of the army of volunteers to keep the crowds in check as the race pounds through London.

He is also the director of sport at Bradford Grammar School – and proud supporter of two famous old boys.

It will be hard for Lines to keep his emotions in check should Alistair and Jonny Brownlee be leading the field towards medal glory.

“I’m not too sure of the etiquette for marshals,” he laughed. “But I’m sure you’re allowed to cheer.

“I should get a good view, though, because I will stop everyone else back behind me!

“Of course I’ll be giving a round of applause for all the athletes. But then nobody told me off when I shouted out during the test event.”

Meanwhile, Tony Kingham will join two coach-loads from the Brownlees’ athletics club Bingley Harriers among the throng lining the capital’s streets.

Insider knowledge should get them the perfect view of what would be a dream one-two for the district.

Kingham, like Lines, goes way back with the brothers. He was the driving force behind the school running club where both honed their considerable talents.

He said: “In a sense, the result is almost immaterial. Both enjoy what they are doing so much.

“I’ve got such confidence and faith in their ability. I can believe anything of those two boys.

“They both seem capable of making the next step they reach and then moving on. While they are exceptionally level-headed, there is also this passion for getting better and better.

“The way they’ve progressed in the last four or five years has been phenomenal.”

Kingham and Lines are too modest to trumpet their own part in the rise of the Brownlee brothers but the school’s stamp on their progress is clear.

Alistair, in particular, was encouraged by the strength and keenness of the team around him.

Kingham recalled: “Alistair was certainly one of our outstanding ones and the only English schools champion I ever had.

“But there were several boys in his year who were very good runners and that strong team pushed each other along.

“Alistair was Yorkshire champion from the age of 13 and every year after that. Jonathan wasn’t quite so lucky with his year group but he was always in the top three or four.”

Lines admits their classroom mates were often “mesmerised” by the sight of the brothers pedalling into school in the morning, having ridden all the way from Leeds.

He said: “It was the same after school. Everyone else would be going to the station, catching a bus or waiting for a lift from mum and dad, but they’d be running or cycling home.”

The Brownlees remain just as grounded as those school days. According to Kingham, the only time Alistair feels the pressure “is when someone asks him about feeling the pressure. Otherwise it doesn’t enter his head and Jonathan is much the same”.

Out on a training run the night before the test event, the brothers spotted Lines walking through the park and just stopped for a chat.

He said: “That’s just typical of them. They will stop and talk to anybody. That’s one of their great traits that has never changed. Win or lose, they’ll do their best and be happy with that.

“With their ages (Alistair is 24 and Jonny 22) you would hope they would have at least another Olympic cycle to go. “But there is no doubt they could be first and second on the day, which would be incredible. In fact, a photo finish might be nice…”