Alistair Brownlee helped stricken brother Jonny to cross the line in a dramatic finale to the World Triathlon Series season and then insisted he would have come to the aid of any fellow triathlete in similar circumstances.

Seeking a victory in Cozumel, Mexico that would have secured the world championship title, Jonny Brownlee struggled badly with apparent heat exhaustion in the closing stages of the run, enabling South Africa's Henri Schoeman to win the race.

After staggering towards a race marshal, the dazed Briton swiftly received support from his elder sibling, who wrapped his arm around him and all but dragged Jonny towards the finish before pushing him over the line, where he collapsed to the ground.

In an interview with the BBC, Alistair Brownlee said: "I've been in that position before and, when it happened to me in London all those years ago, I remember sprinting away in second place and then being in the position Jonny's in now and coming round, and someone telling me I was in 10th and being like ' how did all them people come past me?'.

"So I swore, if it had happened to anyone, if it had happened to Henri [Schoeman], I would have helped him across the line, because to be honest, it's an awful position to be in.

"It was a natural human reaction to my brother but for anyone I would have done the same thing. It's dangerous for someone to conk out 1k from the finish line and, as I said, I've been in that position before and it’s as close to death as you're going to be in sport, I think."

Alistair added with a smile: "I wish the flippin' idiot had just paced it right and crossed the finish line first.

"He'd won it easy. He could have jogged that last 2k and won the race - but yeah, who am I to talk."

Although second place was not enough for Jonny to earn the world title, that honour instead going to Spain's Mario Mola, the Spanish Triathlon Federation lodged a protest - seeking the former's disqualification for accepting assistance to finish.

The appeal was unanimously rejected by the ITU competition jury, with rules stating that athletes can receive help from another athlete or official.

Jonny went on to thank his brother on Twitter, posting: "Not how I wanted to end the season, but gave it everything. Thanks @AliBrownleetri, your loyalty is incredible."