Jess Anderson
BBC Sport in Paris

Right, bear with me for this bit as it's a bit complicated.

There are two groups of eight semi-finalists in each of the men's and women's categories. They will each race three times on the track and the aim is to earn as few points as possible.

Riders are given points according to their position after each race, so you get one point for finishing first, two for finishing second and so on. The eight riders across the semi-finals will progress to the final.

What also makes it pretty complicated is that they will all re-seed after each race as we go along. Oh and we alternate between men's and women's races throughout the evening. Just go with it.

The final is much less complicated and consists of just one winner-takes-all race. Phew.

Craig Heap
Commonwealth Games gold-winning gymnast on BBC TV

Image source, Getty Images

Zak Perzamanos showing good control, settling in.

In he has a very difficult routine, he shows a big extension, on the triple half turn - this is packed with difficulty. He is staying very central and what a routine!

He is pumped. If he can break into the top six he is making history for GB.

That was a tough heat for GB's Phoebe Gill but the 17-year-old had enough left in the tank on the straight to take third place!

Ethiopia's Worknesh Mesele wins this third heat, with home athlete Renelle Lamote in second spot.

Here comes GB's Zac Perzamanos.

A few bounces to settle himself and off he goes!

Sonia Oxley
BBC Sport in Paris

Zak Perzamanos is going to be performing first in this trampoline final - he's got the chance to set the bar but also has a long wait to find out if his score will be enough for a medal.

Can he be inspired by Bryony Page's earlier gold in the women's event and win a first GB men's trampoline medal?

So eight will jump. They will do 10 skills in around 20 seconds and will be scored on difficulty, execution and time in the air.

Team GB 800m athlete Jemma Reekie, speaking to BBC One: "It wasn't the plan today, but I take it as it comes. I am in good shape to run out whatever way."

On her PB and Scottish record of 1:55.61time ran in London two weeks ago: "I managed that run in London and it shows when it matters, but now I have to negotiate the semis which will be tough."

On the track: "It is so nice and those finals are going to go fast!"

Jess Anderson
BBC Sport in Paris

Welcome to Stade BMX in Saint-Quentin-en-Yvelines, some 16 miles south west of Paris - which roughly translates to two pretty long train journeys.

Situated right next to the Velodrome, which will host Paris 2024's track cycling, the BMX stadium has been given a bit of a face lift for the Games and looks in superb order all trimmed out in purple.

Image source, BBC Sport

If you're new to this sport, strap in. It's a full-throttle, tense, exhilarating, adrenaline ride around a 400m track with various jumps, rollers and banks.

I have to say of all the sports at this Games this is the one I would love to have a crack at. It just looks so fun. But I guarantee the way I ride round this track would not be the same as these guys ride round it.

The athletes drop in from the approximately eight metre-platform, which you can see in the background of the below picture, and pelt round the track to try and be the first to cross the line, while we all essentially hold our breaths.

Image source, BBC Sport

The first one to go through this lovely multi-coloured arch wins. Who fancies it then?

Image source, BBC Sport

BBC One

Get the remote ready, you need to switch over to BBC One now to watch the remaining women's 800m heats.

Allison Curbishley
Athletics expert on BBC Radio 5 Live

Really controlled running from Jemma Reekie, she never looked fazed at all.

BBC Sounds

Image source, PA Media

Phoebe Gill, at just 17 years old, is Team GB’s youngest track athlete to compete at a Games for more than 40 years. Hear her story in Paris: Grassroots to Glory here.

Gill will be on our screens next in the third heat.

We have to wait a little bit now, as Tokyo 2020 800m silver medallist Keely Hodgkinson goes in heat four.

Keely Hodgkinson, 22, already has an impressive collection of medals.

She has already been a two-time European champion. Can she become the Olympic champion in Paris?

Dame Denise Lewis
Athens 2000 Olympic heptathlon gold medallist on BBC TV

Nice to be in control and make light work. It was a good run and I liked it. Invigorating Jemma Reekie running.

Harry Poole
BBC Sport in Paris

Image source, Getty Images

The mixed 4x400m relay quartet have got Team GB off to a great start in this first evening session of athletics.

Will we see more of the same in the women's 800m heats?

Keely Hodgkinson, Jemma Reekie and teenager Phoebe Gill - GB's youngest Olympic track athlete for 40 years - will each bid to reach Sunday's 800m semi-finals shortly.

Hodgkinson and Reekie are the two fastest women in the world this year, while Gill has set a European junior 800m record in a stunning breakout season.

It's also worth keeping an eye on world champion Mary Moraa in heat five, with the Kenyan likely representing Hodgkinson's major obstacle to gold in Paris in the absence of Olympic champion Athing Mu, who will not be defending her title after suffering a fall at the US trials.

Paula Radcliffe
Former women's marathon world record holder on BBC TV

Jemma Reekie just needed to get through this round, not with ease but feeling good and strong.

The top three go straight through in these heats and Great Britain's Jemma Reekie is one of them.

Reekie wins in a time of two minutes flat, Gabriela Gajanova of Slovakia is second and the USA's Juliette Whittaker is third.

Image source, Getty Images

Canada's Gabriela Dabrowski and Felix Auger-Aliassime are Olympic bronze medallists.

The mixed doubles pair claimed a 6-3 7-6 (7-2) victory over the Netherlands' Demi Schuurs and Wesley Koolhof.

The gold medal match will take place on Court Philippe Chatrier after this encounter between Novak Djokovic and Lorenzo Musetti is settled.

They could be made to wait - Djokovic and Musetti remain on serve in this first set.