GB's Callum Hawkins comes across to grab a drink from the latest feeding station. He is just starting to drop away a bit from the leading group.

Further down the field Ben Connor is 88th and Chris Thompson is 96.

Jo Frazer-Wise: It’s amazing that even now as a very slow marathon runner after 13 marathons this is the one event I can really relate to - training, pace, fuel - all the same things every marathon runner thinks about!

Eliud Kipchoge's world record time is 2:01:39. That won't be troubled today because of the conditions but we're looking at around a 2:09:00 marathon time.

Oh Joohan stops and walks for a moment, sweat pouring off his head. He tries again to get running but it looks like it isn't going to happen. He was in that leading pack before pulling up.

David Hawkins: Really enjoying the coverage of the men’s marathon. My own PB of 3:46 (1998) wouldn’t be enough to trouble these guys, but I do appreciate all the training/preparation that goes into a marathon. These guys are phenomenally fit, believe me.

London 2012 marathon winner Stephen Kiprotich has now stopped running. It may be a touch cooler in Sapporo but still tough conditions with 26 degrees temperature and 76% humidity.

Steve Cram
Athletics commentator on BBC TV

He is not that far adrift, still early stages and he may be running to a game plan. We don't know the game plan but he is not too far adrift.

Paula Radcliffe
Women's marathon world record holder on BBC TV

Callum is close to his personal best, they are not disappearing up the road yet.

Callum Hawkins is the highest-placed Brit in 49th place, seeing off the 10km mark in 30:59.

The runners have just past the latest feeding station, one runner wisely whacking some ice under his cap.

Shura Kitata has pulled up already with what appears to be cramp. That is a surprise as he's one of the favourites to challenge for a medal.

Simon Gleave, head of sports analysis, Nielsen Gracenote: "Great Britain have ended the penultimate day of Tokyo 2020 with 63 medals, one more than at this stage at London 2012 and three fewer than Rio 2016 after 15 days. The 20 gold medals are seven behind Rio and eight behind London. The final day in Rio delivered Joseph Joyce's boxing silver medal. In London, Anthony Joshua won boxing gold on the last day amongst three medals.

"This year though, there are track cycling events on the last day with Jack Carlin and Laura Kenny as strongest potential medallists. In addition, Team GB have a guaranteed 64th medal from Lauren Price and Callum Hawkins amongst the best marathon runners."

Image source, Getty Images

On Great Britain v ROC for fourth place:"As expected, ROC won three gold medals to overtake Great Britain on the medal table on day 15. Both have 20 gold medals but ROC have won five more silvers. On Sunday, ROC have two opportunities to win golds - in rhythmic gymnastics and handball. Russia won both of these events at the last Olympic Games and are favourites to win both again. To finish fourth on the medal table, Great Britain probably need to win two gold medals on Sunday and hope that ROC do not win both of these events."

The runners have just passed the 5km mark, the leaders smashing it out in just over 15 minutes.

That's about six minutes quicker than my 5km best but that's with me collapsing on the floor and struggling to breathe for 10 minutes afterwards, this lot still have more than 35km to do!

For what it is worth Jeison Alexander Suarez is the current leader, but it is far too early for any leader talk.

Paul Higgs: Clearly none of these Olympic marathon runners have a sense of humour. Not one of them have dressed up as a duck, Big Ben or a hot dog.

Good to see spectators lining the streets of Sapporo - there's not loads but enough to create a bit of an atmosphere as the runners pass through.

Eliud Kipchoge is the favourite for this race as he hopes to become only the third man to win consecutive marathon golds.

An Olympic title is not all that is on his mind.

"My real excitement in Tokyo is no longer about competing at an Olympic Games, it is about making a legacy," he says.

Pentathlete Joe Choong won Great Britain's 20th gold medal of the Tokyo Games after boxer Galal Yafai became an Olympic flyweight champion on Saturday.

Choong followed Kate French's victory on Friday in the women's event by becoming the first British man to win individual modern pentathlon gold.

Josh Kerr in the 1500m and diver Tom Daley won bronzes, with silver for cyclists Matt Walls and Ethan Hayter.

BBC One

The men's marathon is under way!

More than 100 athletes from 40 nations taking part in this one. It is live on BBC One right now.

Nick Hope
BBC Sport Olympics reporter in Sapporo

We are 700 miles north of Tokyo here in Sapporo. It moved up here because of cooler conditions. It is around 26, 27 degrees at the moment with a cool breeze. There is quite a lot of cloud cover and we are hoping that stays for what will be challenging conditions for the athletes over the next couple of hours.

In total there are 13 medals up for grabs today. Here's some of the things to watch out for.

• Track cycling: Laura Kenny in omnium (from 02:00 BST)
• Track cycling: Jason Kenny and Jack Carlin in keirin (from 02:25 BST)
• Basketball: USA face Japan in women's final (from 03:30 BST)
• Boxing:Four finals with Lauren Price in women's middleweight gold-medal fight (from 06:00 BST)
• Also medals in beach volleyball, water polo and handball
• Tokyo Games draw to a close with closing ceremony at 12:00 BST

Ryan Glendenning: Wow I can't believe it's the last day of the #Tokyo2020, external Olympics it's gone so fast. However #TeamGB, external has surpassed expectations and have had another great games again well done @TeamGB, external I feel so proud to be British.