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

I have no idea why Divine Oduduru has been disqualified and Reece Prescod wasn't, but the starters will have their reasons.

It's Nigeria's Divine Oduduru at fault for that one and he's been disqualified!

He's shaking his head as he leaves the track. His reaction time was slower than Reece Prescod's on the first false start yet the Brit is still in the competition.

Count those lucky chickens.

FALSE START AGAIN! Oh my word.

And breathe. The green card is shown and the full line-up can go again. Reece Prescod is a lucky boy.

Take two.

FALSE START!

That could have been Reece Prescod...

It's a cracking line-up in heat five of the men's 100m.

Reece Prescod goes for GB, taking on the likes of Fred Kerley of the US and Canada's Andre de Grasse.

Guy Hornsby: So gutted for Dina. Something didn't look quite right but we don't know what's going on just watching. I just hope she's ok, for herself first and the 200m coming up. Whatever happens here, so much love for this brilliant athlete and human.

The first field final of these Olympics is about to start - the men's discus final.

Sweden's Daniel Stahl comes into this final as the top-ranked athlete. The world champion has won 11 of his 13 competitions this year and has set a world lead of 71.40m.

He'll take some beating today, but look out too for Kristjan Ceh of Slovenia. He's also a fully-fledged member of the 70m club.

Image source, Getty Images

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

It was a good performance from Gift Leotlela, he came down from altitude down to sea level and takes on the might of Su.

He took that victory in a very calm and controlled manner. Just does everything accurately, no panic whatsoever.

Heat four of the men's 100m is won by South Africa's Gift Leotlela in 10.04.

China's Su Bingtian is second, one hundredth of a second back, with Jason Rogers of Saint Kitts and Nevis also progressing.

Lutalo Muhammad
Two-time Olympic Taekwondo medallist on BBC Radio 5 Live

We have seen throughout this entire Olympics a lot of favourites going out before we would have expected - pressure bursts pipes. Perhaps we should have expected it with the lack of crowd noise, these athletes are only human.

Mike Costello
Athletics commentator on BBC Radio 5 Live

For me, one of the most striking noises in sport is no noise. The silence before a 100m final. Are some athletes suffering because of that? Maybe it is a factor.

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

After seeing the indoor series we were just wondering to ourselves, the Italians have a good reputation of 60m running but can they continue that outdoors. [Lamont Marcell Jacobs] has certainly been able to do that.

All of those races under your belt at a very high quality, matter.

Debbie M: Oblique Seville can join Zac Stubblety-Cook in the cool names club

It's a new national record for Italy's Lamont Marcell Jacobs in heat three of the men's 100m. He wins the heat in a time of 9.94.

Jamiaca's Oblique Seville and South Africa's Shaun Maswanganyi are also through to the semis.

Simon Gleave
Head of sports analysis, Nielsen Gracenote

New Zealand have won their first gold in rugby sevens at their fourth attempt with victory for the women. It is the second Olympic gold medal for New Zealand in a team sport - following their victory in men's hockey at the 1976 Games.

France's silver medal in women's rugby sevens is the country's fourth rugby medal at the Olympics, following gold in 1900 and silver in 1920 and 1924 in rugby XVs. France have more Olympic medals in rugby than any other country.

Dame Jessica Ennis-Hill
London 2012 Olympic heptathlon champion on BBC TV

We came here thinking there would be some disturbances and some anomalies from the year we have had but we have seen some great performances to this point.

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

We have been mentioning scripts, they have all been torn up today. What a surprise.

I expected Trayvon Bromell to come out of the blocks and just cruise, and that just didn't happen.

We have watched him in the Diamond League circuit and he is a bit sketchy and then he races himself back in. Perhaps he just has to do that here as well.

Nigeria's Enoch Adegoke wins heat two, with Qatar's Femi Ogunode second and GB's Zharnel Hughes third in a season's best time. All three are through to the semis.

But Trayvon Bromell, well...he's pipped to the line by Hughes and finishes fourth. He must wait to see if his time is fast enough for a fastest loser spot in the semis.