jmox1234: I'm glad the Brownlees have different coloured handlebars. Jonny wrote that Alistair once accidentally rode off with his bike!

The triathlon pack hit the Atlantic in a white wave.

Alistair Brownlee did not get the cleanest start off the beach, but Slovakia's Richard Varga - who trains with the Britons in Yorkshire - has gone into an early lead.

Dives three of five are complete, and it's been Tonia Couch's best dive so far. A nice piece of mid-air flipping moves her up to thirteenth place with a total of 182.60 points. She's roughly five points away from the top 12, which would secure her a place in tonight's final.

China's Si Yajie is leading the pack by a long way with a big total of 238.40 points.

The British Brownlee brothers look relaxed as they chat and stretch goggles ahead of the 1500m sea swim. They will be helped by team-mate Gordon Benson in the water.

Following that it is a 40km bike ride and a 10km run to finish.

The start is seconds away. 

Since triathlon was introduced into the Olympics in 2000, no athlete has ever won twice.

Legendary ITU Canadian athlete Simon Whitfield came close in Beijing 2008 with a silver medal... 

A very tight opening game in the bronze medal match but it's gone Marcus Ellis and Chris Langridge's way. 

They are 1-0 up against the Chinese pair of Biao Chai and Wei Hong and are attacking hard 

If you have never watched badminton before, watch here. It really is something... 

Bottle?

Cleets?

Skid lid? 

Final bike checks for the Brownlees.

They won't be getting any help from these lot though who have turned up in support of Spain's Mario Mola and Fernando Alarza.

Nick Hope
BBC Sport in Rio

Image source, .

Well, that will have helped work off some of the nerves this morning! 

Jade Jones beats Naima Bakkal of Morocco 12-4 and heads into this afternoon's quarter-finals.

An Olympic title defence is such a different challenge to the one she faced four years ago as a 'rising star'.

Since her London success every -57kg fighter has studied her style and Jade's had to make big adaptations to her technique and learn a host of new moves.

She looked strong in that opening round, but much tougher challenges await and she'll be up against Iranian born refugee Raheleh Asemani - who's representing Belgium in Rio - at 19:30pm BST.

If you like swimming, running and cycling there is no reason not to give triathlon a go.

With clubs all over the UK, and different age groups and standards to participate in, nothing can hold you back. Use this guide to get you started.

Image source, Getty Images

Image source, Reuters

So far, so good for Great Britain's Morgan Lake, who has registered first-time clearances at 1.80m, 185m and 1.89m.

Her personal best is 1.94m and she is heading that way in smooth style.

If she manages 1.94m she will be straight into the final. If not, she needs a top-12 finish.

Very VERY good play from the British pair here. They are moving well, attacking strongly and the Chinese are not doing much to harm them at the moment. 

There is just one point in it at the mid-game interval. 

That's a better second dive from Tonia Couch, complete with a very stable armstand,and she's moved up to 14th place with 110.60 points.

China's Si Yajie is currently leading the back, with her 15-year-old compatriot Ren Quian in second place.

In their dressing gowns.

Brilliant.

More precision footwork than in a production of Riverdance.

Jade Jones picks off Morocco's Naima Bakkal with some balletic, ballistic kicks to the head.

12-4 the final score as the Welshwoman ploughs into the last eight.

Image source, BBC Sport

Okay, they may be good but not that good.... 

This is them warming up at Copacabana Beach. 

They start their swim at 15:00 BST... 

Can Ali retain his Olympic gold from 2012 or does little brother Johnny have a cunning plan up his long sleeve...?

Brothers Alistair and Jonny Brownlee attempt to defend their Olympic gold and bronze medals in the men's final in Rio this afternoon.

In London 2012, Jonny was pipped to silver by the brothers' biggest rival Javier Gomez, after picking up 15-second penalty for mounting his bike too early. 

No danger of that today as July Gomez withdrew from Rio after breaking his arm in July.

The brothers biggest competitors in this race are the two top ranked Spanish athletes: Mario Mola who has won four of the nine ITU series races and is currently ranked first, and Fernando Alarza, who is ranked second in the world series with two more races post-Olympics. 

Today the race for gold is likely to be down to the run with Mola's sub 30 minute 10km to test the reigning champion.

Great Britain's Jade Jones takes a lead from the first round of her opening bout, the highlight being a three-point kick clean on the chin of her Moroccan opponent Naima Bakkal.

"In my opinion this pair have a real chance of taking bronze today as this Chinese pair can get very nervous" says commentator Gill Clark.

It's currently 5-5 to the Chinese in the first set. 

Watch live here.