Image source, Getty Images

Two-time Olympic champion Alistair Brownlee: "Every day has been so hard. I have woken up in pain every day it has been so hard.

"The swim wasn't that quick but we knew the first two laps on the bike would be crucial. The last few weeks we have been training to commit and boy we did. 

"As soon as we got to half way I knew we were going to get two medals and it was just a run for it. 

"I was pretty confident we would get first and second but I didn't know which way round it would be. I just had the edge on Jonny but he has killed me in training every day and I have been going through hell every day." 

Image source, Getty Images

ChrisMurray18: Imagine being Jonny Brownlee, 2nd best triathlete in the world and not even the best in your family

C Cret:, external Why can't my children be competitive in a good way like the Brownlee bros instead of always trying to maim each other

Kate Evans: Full of Yorkshire pride for the Brownlees. Yorkshire's finest brothers. Their parents must be so, so proud.

This is very much a pair of medals that were born, bred and belong to God's own county.

Expect Yorkshire Post to be recalculating the medal table, with at least another bronze to come from Nicola Adams as well.

Annie Emmerson
BBC Sport triathlon expert & former GB triathlete

Alistair is the greatest all-round triathlete of all time, we can safely say that.

He has come from adversity. He has had huge injuries, surgery just a few months ago and to come back with a result like that is unprecedented.

The grimaces are turning to grins.

Alistair is sipping isotonic and soaking up the glory and lactic.

Annie Emmerson
BBC Sport triathlon expert & former GB triathlete

It is amazing. To execute the best race of your life in your second Olympics, it is absolutely  amazing. 

We were all worried looking at the conditions but wow, I don't know if Alistair is surprised himself but the early stages on the bike really counted. 

Jonny was amazing but he is just not able to equal his brother. Alistair is so mentally strong.

Alistair Brownlee wins Great Britain's 20th gold of the Games and becomes the first man to defend an Olympic triathlon title.

Great Britain are clear of China in second place in the medal with 20 top gongs compared to their 19. 

What a performance.

What a champion.

What a family.

Absolutely superb from the Brownlees as they rule the triathlon world once more.

Annie Emmerson
BBC Sport triathlon expert & former GB triathlete

An absolutely stunning race from Alistair Brownlee. A perfect race. The story of the Olympics so far?

British flags are being offered to Alistair Brownlee.

He's taken one!

And a Yorkshire banner.

This is done.

With 20 seconds separating him from brother Jonny, Alistair Brownlee is now picking off the backmarkers.

This is taking on the feel of an in-race victory lap.

Chris Roche: #Brownlees doing brilliantly, again! Great athletes, great inspiration.

Pauls: I'm exhausted watching the triathlon Brownlee brothers are amazing.

Annie Emmerson
BBC Sport triathlon expert & former GB triathlete

It has got to be frustrating for Jonny.

He is a phenomenal athlete in his own right but he has got to be thinking 'what do I have to do to beat my big brother?'

It doesn't look like it will happen today.

It looked as though the Olympic champions were goners after dropping the baton in their heat, but an appeal has been successful and they will get another chance at 23:00 BST. Apparently, the US quartet "will have to run faster than China's 42.70 from the heats".

Image source, Getty Images

Inspired by the Brownlee brothers?  There's a triathlon out there for everyone, even children! Give it a go with Get Inspired's guide.

Prepare the finishline welcome committee.

Alistair Brownlee hits the bell for the final 2.5km lap with a 15-second advantage on brother Jonny.

It will take a major meltdown to deny him a successful defence of his Olympic title.

Henri Schoeman is another 23 seconds behind Jonny in third.

Great Britain looking very good for a gold-silver double.