Aimee Lewis
BBC Sport in Rio

The shot put is taking place at one end of the stadium, while at the other spectators are more interested in starting a Mexican wave. Shot putters, the bass guitarists of track and field, if you like - we'd miss them if they weren't here, but they do, at times, get overlooked. Anyway, it's a poor attempt at a Mexican wave, so we might as well focus on the only competition currently taking place in the stadium. 

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Favourite Joe Kovacs has just thrown his first effort of the night out to 21.78m to take the early lead. Will anyone eclipse that?

Bolt in Bejing. Bolt in London. Johnson in Atlanta. Lewis in LA.

The 200m final has thrown up some really huge Olympic moments, and that BBC montage gathered them all in nicely.

Anyone's favourite event? I remember thinking that Michael Johnson's 19.32 would never get beaten.

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Three-and-three-quarter laps of the track. It's the distance that perhaps makes the least sense - why not 1600 or 1200m? - but it can produce a brilliant combination of tactics and sprint finishing.

GB have two men in action tonight, one in each semi-final.

Charlie Grice runs in semi-final one (00:45 BST) and Chris O'Hare goes in number two 10 minutes later.

The top five finishers in each semi make it through to the final on Saturday.

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

"I am looking forward to the 200m race that's going to happen behind Usain Bolt. I think there will be a real battle for those medals. Usain sucks up all the attention in the room but there are some good guys there behind him."

"I definitely think I can try for the world record, I definitely feel that."

Those were the words of Usain Bolt last night after his semi-final win. Can he really threaten the 19.19secs he set in 2009?

Aimee Lewis
BBC Sport in Rio

 Imagine coming to Rio to watch the Olympics and not having to pay a penny for it. Well, Jarno Metsäranta (pictured left) doesn't have to because he's here courtesy of winning a competition with a betting firm in Finland. 

It's an all-expenses paid holiday of a lifetime, and he'll get to watch Usain Bolt compete in his last individual Olympic race. What a prize. 

"I've never seen him before so It's very exciting to see him live," he says of Bolt. "It will be so different than seeing him on TV."

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Best laid plans, and all that.

The king of the Netherlands has been flown out to Rio to present the medals for the women's 200m. Dutchwoman Dafne Schippers was the favourite but she was beaten by Elaine Thompson. Awkward. 

Gareth Murphy: Trying to convince people to stay up. Jade Jones on at 0200 n Bolt at 0230 and expert punditry especially from @MJGold, external is reason enough.

Sam Holloway: What do you mean, you're going to sleep now and setting an alarm for 0230? That's cheating! I'm in for the long haul. 

There are 44 points between gold and silver, and 44 points between bronze and fourth place.

Should be a thrilling 1500m finale at about 01:56 BST. 

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

When you are talking to Usain Bolt one-on-one he is really quite shy but out on the track when he is away from everyone else he becomes confident and enjoys this.

I don't think we will see another Bolt - a combination of being the athlete he is and the entertainment that he brings.

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Leonel Suarez ends his decathlon with a throw of 72.32, not far away from his own Olympic best of 76.94m.

Keisuke Ushiro nails his last effort out to 66.63 - the second best yet - and he's delighted! He sprints away back to his coach, absolutely loving it.

Ashton Eaton, a sprinter, not a natural thrower I'd suggest, is tentative on approach but he does manage to improve, out to 59.77m.

He will lead going into the 1500m finale. 

The great man  himself Usain Bolt is now in the warm-up area, headphones on, jiving and dabbing away. He pauses every 30 seconds or so for a photo, a handshake.

Nerves? I don't think so. 

Aimee Lewis
BBC Sport in Rio

I know everyone loves a Usain Bolt anecdote so let me tell you about a wedding in Jamaica which came to a standstill this week for the 100m final. 

"A friend of mine went to a wedding in Jamaica," says Cecile Lee who has travelled from Jamaica to support the track and field team. 

"The reception stopped when he was racing, even the bride and groom were watching! She told me 'only in Jamaica could that happen.'

"He's a wonderful ambassador, he's charismatic, and a really wonderful person. He loves people and the sport and we admire him for that. It will be pandemonium back in Jamaica if he wins tonight."

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The first athletics medal this evening will be decided in the men's shot.

Joe Kovacs - last year's world champion - leads the rankings so far in 2016 with a best of 22.13m. 

No Brits involved tonight. 

Big! Leonel Suarez lands one at 70.05m, the furthest we've seen in this men's decathlon javelin so far. 

Aimee Lewis
BBC Sport in Rio

There are people in this stadium who will see Usain Bolt compete for the first, and last time, and they're quite excited about it.

"He's a phenomenon," says Gustavo, from Porto Alegri in south Brazil. 

"It's my unique chance to see the guy. He's the fastest man in world and it's something I'll tell my children and grandchildren. Today is history."

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