Worth watching just once more before you head to bed.

It wasn't the storyline most wanted, but it was the whole lot more dramatic.

Join us tomorrow for the conclusion of the heptathlon and a 100m final where Jamaican Olympic champion Elaine Thompson will attempt to take up the title that her pregnant compatriot Shelly-Ann Fraser-Pryce won in 2015.

Bye for now.

A lot of talk about the rights and wrongs of drug bans tonight.

If you are feeling a little down and deflated, you should take five minutes to read the back story of long jump world champion and reformed crystal meth addict Luvo Manyonga right here., external

There are inspiring stories out there tonight if you want them.

The medal ceremony for the 100m final is tomorrow.

Quite possibly just after Jessica Ennis-Hill is handed up upgraded gold after being beaten by a doped Tatyana Chernova at the 2011 worlds.

The atmosphere for that should be...interesting.

Image source, Getty Images

The awkward part about Justin Gatlin's victory for even the most forgiving observer is that the science suggests that once 'dirty' as an athlete, you can never get clean.

Research by University of Oslo, external scientists in 2014 established that muscles can retain the advantages given by anabolic steroids decades after the point at which they were taken.

But, that whole 'twice-banned doper' tag.

Gatlin failed his first test in 2001 when amphetamines were found in his samples at the USA Junior Championships.

But it was accepted that medicine he had been taking for 10 years to control attention-deficit disorder was the reason for the failed test.

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

Bolt will have been very disappointed with that. He didn't perform how he knows he can. He will look at the clock and realise he was capable of a winning time. But we can't judge his career on this.

Image source, Reuters

Denise Lewis
Olympic heptathlon gold medallist on BBC TV

Justin Gatlin has been through the mill and whatever side of the fence you sit on, it is sport. He was crying and that moved me. He has worked hard. He still has to train as hard as everyone else and turn up and deliver.

Mr Tooze: Torn with the #bolt, external result. The whole idea of reform & changing character is defunct if you can't accept Gatlin's win

Image source, PA

Usain Bolt, talking to BBC Sport: "When I got out you have to transition. I didn't get the power in that transition. I tightened up at the end and that is something you should never do. It is just one of those things. I didn't execute when it mattered.

"I am not fully comfortable in those blocks but you have to work with what you have. I can't complain about that.

"He (Gatlin) is a great competitor. You have to be at your best against him. I really appreciate competing against him and he is a good person."

Patrick Green: I do have space in my heart for Justin Gatlin. Congratulations, the fastest man on Earth

Alex: Well done #Gatlin, external on your gold medal seeing as everyone else is focused on #Bolt, external

Image source, Getty Images

World champion Justin Gatlin: "I tuned it out (the boos) through the rounds and stayed the course. I did what I had to do. The people who love me are here cheering for me and cheering at home. I thought of what I would do if I did win but I didn't do any of that.

It is Bolt's last race. I have had many victories and many defeats down the years. It is an amazing occasion. We are rivals on the track but in the warm-down area we joke and have a good time. The first thing he did was congratulate me and say that I didn't deserve the boos. He is an inspiration."

Michael Johnson
Four-time Olympic gold medallist athlete on BBC TV

He has never really had a great start. He wasn't able to close the gap. Once he gets up into his running is when he is able to take advantage of the long stride and close the gap.

He is grimacing and that is something we have not seen before. You will not find that look in all the archives of Usain Bolt.

He is a great technician and tactician but when you come under that pressure there is nothing to do but go to that athleticism.

Image source, gett

How much does tonight really matter in the end?

This won't be the race that Usain Bolt's career is defined by.

His legacy was secure long ago. Tonight we saw another side of the sportsman - how he could take defeat and disappointment.

And he was pretty good at that as well.

Usain Bolt, speaking to BBC Sport: "This was wonderful. I knew they would come out and support me. I'm just sad I couldn't come out and win.

"My start killed me. Normally I get better through the rounds but it didn't come together. The fact I didn't get it is why I lost.

"The support has been outstanding. They have stood behind me and pushed me and I really appreciate that."

Rory Moir: Shame Bolt couldn't finish his career with a final gold but what a legend of the sport he's been!

Alan C. Smith: We wanted the fairy tale. The Legend is just a man. A Legend written a long time ago. #immortal, external

Adam O'Neill: Usain Bolt will forever be classed as a legend in the sport of Athletics. As for Gatlin, the less said the better