Image source, Getty Images

At the end of the fourth stage of the pentathlon, GB's Choong has a 12-point lead on Jung Jin-Hwa in second place, finishing on 859.

Jan Kuf of the Czech Republic is in third with 838, 21 points behind Choong and nine points behind Jung.

GB's James Cooke is in ninth place with 824 points.

It's not over though. There's still plenty to for in the final stage!

Can Team GB sign off from Tokyo 2020 with a sixth equestrian medal?

It's time for the showjumping team event final, with Britain's Holly Smith (Denver), Harry Charles (Romeo 88) and Ben Maher (Explosion W) qualifying seventh.

Maher, who was part of the team that won gold at London 2012, is seeking a second medal in Tokyo after winning the individual competition.

Keep an eye out for Team USA. The Americans have been the most successful team in the 21 century and have Jessica Springsteen- daughter of singer Bruce - competing.

Great Britain's Galal Yafai got a call from his brother shortly after winning gold this morning.

This is brilliant!

Peres Jepchirchir won the women's marathon to kick off day 15 as Kenya claimed a one-two in sweltering conditions in Japan's northern city of Sapporo.

Jepchirchir beat world record holder Brigid Kosgei in the closing stages to win in two hours 27 minutes 20 seconds.

American Molly Seidel took bronze and Stephanie Davis, the 2021 British champion, finished 39th in 2:36:33.

Contested in 28C heat, the race was moved from 07:00 to 06:00 local time because of the forecast temperatures.

The showjumping team final gets under way at 11:00 BST and Great Britain are after a medal.

The gold-medal match between Japan and the USA in the baseball takes place at the same time.

And the athletics kicks in at 11:00 BST too, with eight medals up for grabs.

Great Britain's Morgan Lake is in the women's high jump and Eilish McColgan and Jess Judd go in the women's 10,000. The men's 1500m and men's 4x400m relays are also taking place.

The conclusion of the men's pentathlon follows at 11:30 and the gold-medal football match between Brazil and Spain kicks off at 12:30.

Busy morning!

It was a sloppy start from Choong but he recovered well and finished with 286 points.

GB's hopes of a clean sweep in the modern pentathlon continue, as Choong remains top of the leaderboard with 859 points!

There's just one round to go - the laser-run.

While all eyes this morning have been on Galal Yafai and his flyweight gold medal, there's been a spectacular knockout in the men's middleweight final.

Ukraine's Oleksandr Khyzhniak was well ahead on the judge's scorecards before being caught by a left hook from Brazil's Hebert Sousa.

If you're following the BBC One coverage, they are showing Galal Yafai's gold medal.

The Briton won the flyweight boxing event and that was followed by Tom Daley's bronze in the men's 10m platform diving.

Not a bad morning.

Team GB

Jason Kenny also spoke to BBC Sport after he qualified in the repechage:

"I felt a lot better in the rep[echage] and had to go the long way round but I’m through.

"Normally I feel happy I have a bit more recovery as the clean up after a crash. People are throwing everything at it. It’s just the way it is.

"I keep chipping away and try not to give anything away easily. I felt a million dollars and really chuffed to come through the other side."

On his wife Laura Kenny's gold medal in the women's madison:

"There was only one team in it from the start – really chuffed for them. I've seen them working hard for it in Manchester and they got it bang on. Put them at completely another level."

GB's James Cooke scores 293 on Discastino.

The horse looked a little sluggish but Cooke drove him on to seal a solid score.

Joe Choong is yet to jump.

If you missed all the "chaos" earlier, here it is.

Team GB

Team GB's Jack Carlin talks to BBC Sport after some eventful rounds in the men's keirin.

"It was absolute chaos to be honest with you. Everyone wants it so badly they’ll do anything. It’s racing. I don’t think I did anything wrong in either of the moves, I tried to stop myself falling off. We have the video to see what we were doing. People were trying to find the easy way round and riding too close together.

"You can’t blame anybody there’s been times I’ve been on the end as well. There’s points I was just closing my eyes and hoping for the best but we go again."

GB's Joe Choong will be jumping on Clntino, who Kate French also rode yesterday on her way to Olympic gold.

Choong was leading the way as we started the fourth round of the pentathlon but is yet to jump.

Fellow Brit James Cooke will be on board Discastino, as he hopes to move up the leaderboard from 10th place.

The horses are randomly selected remember ... so can Clntino match yesterday's performance for Choong?

Team GB

Great Britain's Matt Wall and Ethan Hayter, who won silver in the men's madison a short while ago, spoke to BBC Sport:

Matt Wall: "I was just cooked half way in at least. We had a bit of gas at the end just to finish it off."

Ethan Hayter: "We sat out on the front to try and get a head start but I just felt my legs go first because the first 100 laps were so hard.

"I started to suffer, then Matt started to suffer. Recovered and finished with a flourish."

A disappointment for Katy Marchant but there's been plenty going on this morning. Here's what's happened so far on day 15...

• Britain's Galal Yafai won Olympic flyweight gold with an impressive victory over Carlo Paalam, knocking down his opponent after only 90 seconds on his way to a points victory
• Tom Daley has secured his second medal of the these Games with bronze in the men's 10m platform. Cao Yuan took gold and Yang Jian silver
• In track cycling, it was silver for Matt Walls and Ethan Hayter in the madison with Denmark claiming gold
• GB's Joe Choong is leading the men's modern pentathlon with two events to go
• USA secured their fourth straight men's basketball Olympic gold by holding off a late France comeback to win 87-82
• Kenya's Peres Jepchirchir won the women's marathon in sweltering conditions in Japan's northern city of Sapporo
• Nelly Korda took women's golf gold with Japan's Mone Inami winning a play-off for silver and Lydia Ko getting the bronze

Sir Chris Hoy
Six-time Olympic cycling champion on BBC TV

Katy Marchant shouldn't be too down on herself. It's not the way she wanted to go out and the keirin was a blow with the crash.

Everyone is talking about Paris already because it's only three years away.

I think she will go away, lick her wounds, have some downtime and recover. Hopefully she'll be back in three years for more.

Chris Boardman
Olympic cycling champion on BBC TV

Katy Marchant was building that speed going faster and further around the front.

There were a few light changes in tactics but Lee just had that kick that Marchant couldn't match.

She's knocked out of medal contention.

Katy Marchant gets pipped right on the line and that means she is out of the quarter-finals as she lost the first race earlier.

Gutted.

Here is Katy Marchant...

What a thrilling race that was! After Britain's silver in the men's madison, it's just the women's sprint quarter-finals to come in the velodrome.

That features Great Britain's Katy Marchant, who takes on Lee Wai-sze from Hong Kong. It's the best of three so we'll see how she gets on very shortly.

Earlier, Great Britain's Jason Kenny and Jack Carlin both qualified for the men's keirin quarter-finals.