Paula Radcliffe
Women's marathon world record holder on BBC TV in Doha

We've had good success in this event. You just really want her to be able to do it tonight.

You just want to say 'run your own race' and maybe running for a silver or bronze she could actually win it.

So, at last, it's Laura Muir time.

Can the Scot earn her first global outdoor medal?

Image source, Getty Images

Joy for one...

...disappointment for another.

There's no room for Great Britain's men tomorrow's 4x400m relay final.

Colin Jackson
Two-time world 110m hurdles champion on BBC TV in Doha

We knew it was going to be competitive. Once it started to bunch we knew we were going to be in trouble.

France clocked 3:01.40 and they will take the final fastest loser's spot!

Great Britain's 3:01.96 just wasn't enough.

Image source, Getty Images

Jamaica are through first in 3:00.76.

Belgium are second and Trinidad and Tobago third.

What did France do...?

Jamaica anchor Javon Francis is speeding away.

It's a real bundle behind him, though, which could be bad news for GB.

Some elbows on show as the athletes try to squeeze themselves into pole position, but it's Jamaica out in front, with France hot on their heels...

All calm on the first leg, and it's France and Jamaica who come careering out the fastest after the first exchange.

Image source, Gett

How much does that shot put ball weigh again? Seven kilos plus?

New Zealand's Tom Walsh hauls his first round throw out to 22.90m to take the lead - scratching Ryan Crouser's championship record in the process.

It's also the biggest throw since 1990. Sensational from the 2017 champion.

Darlan Romani, Brazil's Diamond League record holder, then goes second with a throw of 22.53m.

This is warming up nicely.

Great Britain are currently in the final fastest loser's spot with 3:01.96.

Is it enough? We're about to find out. Off goes the second heat.

BBC Sport

GB's Martyn Rooney speaking to BBC Sport: "I let these guys down again. It’s a habit I don't like especially people like Lee [Thompson] who works full-time.

"I put myself in a position where I was trying to run just outside lane one all they way. I should have committed one way or the other and I paid for it."

Great Britain will have to wait for the conclusion of this second heat to see if they go through.

Trinidad and Tobago, who claimed gold in London two years ago, will line up in this heat alongside European champs Belgium and Rio silver medallists Jamaica.

Mark: Not being funny but Martyn Rooney never gets his tactics right in the 4x400m Relay. Every single time he lets us down! I know that sounds harsh but it’s been this way for years

G Strachan: Shouldn't have used Rooney on last leg. Yousif better

Saj Chowdhury
BBC Sport in Doha

Martyn Rooney went on a very long walk on his own down the track - he took a metaphorical long hard look at himself.

Will that be the last time we see perennial GB 4x400m anchor man, now 32, compete at World level?

Steve Cram
BBC Sport athletics commentator in Doha

Great Britain are now hanging on by their fingertips. I just thought Martyn Rooney should have attacked that a little bit more.

The USA win that first heat in 2:59.89, with Colombia second and Italy third.

But it's bad news for GB. Martyn Rooney crosses the line in fifth, with Botswana finishing ahead of the Brits.

Nathan Strother immediately powers away from the rest of the field. Martyn Rooney is running well but he's in trouble...here come Colombia and Italy.

After that changeover, Japan and GB move up to the front and Wilbert London drops way back.

Hang on though, the American has found another gear and is motoring back up to the front.

On to the final changeover.