Three runners go down as the penultimate lap comes to the end!

We need a replay of that.

Jakob Ingebrigtsen and Great Britain's Josh Kerr are safely at the front.

Harry Poole
BBC Sport in Budapest

It's not quite a sell-out at the National Athletics Centre, which is basking in the evening sun as the first afternoon session of these World Championships gets under way.

But there's still a great buzz of anticipation around the arena and a mighty roar whips up around the place as the first men's 1500m heat gets under way and continues to follow Jakob Ingebrigtsen and company round the track.

It's warm, up in the high 20s, but very still and perfect conditions for the athletes.

Jakob Ingebrigtsen, in bright pink shoes, starts off by heading to the back before slowly making his way towards the front over the first lap.

Josh Kerr is currently sitting in fourth.

Here we go then for the first race of the night.

Olympic champion Jakob Ingebrigtsen - the big favourite in this event - gets a loud cheer from the crowd.

Britain's Josh Kerr is in this heat too.

The top six go through to the semi-finals.

Heat 1: Jakob Ingebrigtsen, GB's Josh Kerr

Heat 2: GB's Neil Gourley

Heat 4: GB's Elliot Giles, US record holder Yared Nuguse

Image source, Getty Images

Tonight is the start of what could be a special few days for Norway's Jakob Ingebrigtsen.

He is attempting the 1500m-5,000m double - a year after being a surprise second behind Britain's Jake Wightman in Eugene.

Ingebrigsten ran three minutes 27.14 seconds earlier this year which makes him the fourth-fastest 1500m runner in history.

Hicham El Guerrouj's iconic 3:26.00 world record has stood since 1998. Could it go this week?

Ingebrigtsen goes in the first heat at 18:02 BST.

Harry Poole
BBC Sport in Budapest

Budapest’s new National Athletics Centre is a fitting arena for the world’s best athletes to deliver world-class performances.

The purpose-built 35,000 capacity stadium is situated on the Danube River, in a former industrial area which was previously inaccessible due to pollution.

It really is spectacular.

Following the event, the plan is to reduce the capacity to 15,000 with the removal of the temporary upper tier, creating a leisure and sport centre for public use.

We were treated to an upbeat opening ceremony before the start of the evening session. Plenty of tunes, an air show, and a display of flags representing every nation present at these World Championships.

The biggest cheer so far was reserved for the mascot, Youhuu, a native Hungarian racka sheep (as you suspected) who has just run the slowest 100m we’re likely to see this evening to great applause.

Image source, Getty Images

Youhuu, the mascot of the Budapest 2023 World Athletics Championships, has been on the track during the opening ceremony.

Impressive backflips...

Image source, Getty Images

Image source, Reuters

Image source, Getty Images

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

Katarina Johnson-Thompson started off in the hurdles ok, it probably wasn't what she wanted. Kat didn't have that speed or endurance to maintain. It's good to see her come out and run that sort of time. Again, not at her best.

Katarina Johnson-Thompson has her shot put in hand and is just going through a few warm-ups.

Just a reminder the heptathlon gets back under way just after 18:00 BST.

Harry Poole
BBC Sport in Budapest

Since winning her world title four years ago Johnson-Thompson has endured several injury setbacks and even feared her career might be over after rupturing her Achilles.

But a beaming smile on the 30-year-old's face as she found her rhythm in the high jump during the morning session spoke volumes of her current outlook.

And so she should be smiling. After two events, she is absolutely in medal contention.

Next up is the shot put, certainly not her favourite event, but she did throw a personal best 13.92m earlier this year and she’ll hope to replicate that performance here before giving her all in the 200m.

Image source, Getty Images

We've already had some action on the opening day.

In the first session Katarina Johnson-Thompson made a decent start to the heptathlon.

The 2019 champion had a slightly disappointing 100m hurdles but a good performance in the long jump left her fourth overall.

Laura Muir, Katie Snowden and Melissa Courtney-Bryant all progressed in the 1500m, along with big name Faith Kipyegon and Sifan Hassan.

Britain's 4x400m mixed relay team were the second-fastest qualifiers for tonight's final but Jazmin Sawyers failed to make the long jump final.

Harry Poole
BBC Sport in Budapest

The weather was certainly not playing ball this morning as Budapest prepared to kick off the biggest sporting occasion in Hungary’s history.

Those in the city woke to dark, threatening clouds - although that did not dissuade these fans from Finland from a bit of early sightseeing.

We had the odd rumble of thunder before the heavens opened, delaying the opening event - the men’s 20km race walk - and morning track session by one hour.

The adverse weather conditions would not dampen the mood and in a well-attended morning session the heptathletes eventually got the action under way at the National Athletics Centre.

The excitement and anticipation has been building here for some time and, now that we're up and running, it feels as though we could be in for a memorable nine days of competition.

Image source, Getty Images

• 18:02: Men’s 1500m heats, featuring Jakob Ingebrigsten and GB's Olympic bronze medallist Josh Kerr
• 18:05: Heptathlon continues with shot put, including Katarina Johnson-Thompson
• 18:43: Men’s 100m heats - Zharnel Hughes, Fred Kerley, Noah Lyles, Marcell Jacobs
• 19:31: Heptathlon 200m
• 19:37: Men's shot put final
• 19:55: Women’s 10,000m final - stacked field including world record holder Letesenbet Gidey and Sifan Hassan
• 20:49: 4x400m mixed final - GB second fastest in heats

Image source, Getty Images

Ah, the memories. Whether Bolt in Berlin or Dina in Doha the World Athletics Championships has created its fair share.

Tonight the 2023 edition in Budapest ramps up with the first evening session on day one.

Three gold medals will be decided tonight while we'll also see the fastest men in the world and the best female all-rounders in action.

You can watch our TV coverage by clicking play above or follow us throughout the evening for text updates.

The World Athletics Championships... where history is made...

Image source, Getty Images

Image source, Getty Images

Image source, Getty Images

Who will make their mark in 2023?

BBC Sport

There are four gold medals to be won on the opening day of the 2023 World Athletics Championships, with GB’s Jazmin Sawyers and Zharnel Hughes in action.

Morning Session: (07:50 – 12:40 BST)

Men’s 20km race walk

Women’s heptathlon

4x400m mixed relay heats

Women’s long jump qualification

Women’s 1500m heats

Men’s 100m prelims

Afternoon Session: (17:30 – 21:00 BST)

Opening Ceremony

Men’s 1500m heats

Men’s 100m heats

Women’s Heptathlon

Women’s 10,000m final

4x400m mixed final

BBC Sport

GB’s medal hopes are lead by Zharnel Hughes who holds the fastest 100m time this year, smashing Linford Christie’s 30 year British record in June.

800m specialist Keely Hodgkinson and Dina Asher-Smith, the fastest British woman on record, will also be looking to add to Britain’s medal tally.

Other global names competing include Sweden’s pole vault world champion Armand Duplantis, Kenyan long distance star Faith Kipyegon and the USA’s sprinting ace Noah Lyles.

BBC Sport

The 2023 World Athletics Championships take place in Budapest, Hungary at the National Athletics Centre and will feature nearly 2,000 athletes from 180 countries in a variety of events that involve throwing, running and jumping.

The 19th instalment of the Championships, 49 events will take place from the 19-27 August.

Last year’s championships were hosted in Oregon, USA and saw three world records broken alongside another 13 competition records smashed.

The United States topped the medal table in 2022 with a total of 33 medals, including 12 golds. Team GB will be looking to improve on last year’s performance where they finished 11th with a total of seven medals and one gold from Jake Wightman in the 1500m.

BBC iPlayer

The 2023 World Athletics Championships will be broadcast live on BBC One, BBC Two, Red Button, BBC Sport Website, App and BBC iPlayer.

The full TV schedule is below:

(All times are in BST)

Saturday 19th August

BBC Two: 09:00 - 13:30

BBC Two: 17:30 - 21:30

Sunday 20th August

BBC Two: 08:00 - 13:30

BBC One: 15:00 – 18:30

Monday 21st August

BBC Two: 17:30 - 19:30

BBC One: 19:30 – 21:00

Tuesday 22nd August

BBC Two: 17:15 – 20:00

BBC One: 20:00 – 21:00

Wednesday 23rd August

BBC Two: 08:30 – 13:00

BBC Red Button: 17:45 -19:00

BBC One: 19:00 – 21:00

Thursday 24th August

BBC Red Button: 05:50 - 09:30

BBC Two: 17:30 – 20:00

BBC One: 20:00 - 21:00

Friday 25th August

BBC Two: 08:45 - 12:15

BBC Two: 17:30 – 19:00

BBC One: 19:00 – 21:00

Saturday 26th August

BBC Two: 05:55 – 12:00

BBC Red Button: 13:00 - 15:30

BBC One: 18:00 - 21:15

Sunday 27th August

BBC Two: 05:55 - 08:30

BBC One: 18:30 – 21:00