It is an oddity isn't it? All the better for it. Evan Jager of the US hits the front just over the halfway point.

Image source, AFP/Getty Images

Adam Pescod: The steeplechase is a wonderfully random event.

Image source, Reuters

A Chinese record! That's saying something. Changrui Xue leaps over 5.82m, as does Sam Kendricks.

But Piotr Lisek has done 5.89m now. This is hotting up.

Let's get six metres on the board lads. Come on.

Is under way.

Has anybody out there ever done a steeplechase? It's the wild card of track events.

Botswana team doctor Simon O'Brien: "There appears to be confusion. The IAAF report said Isaac had said to the doctor he had vomited at 10pm the previous evening. But Isaac was sat with me.

"When we (Team Botswana) asked whether he said that, he said at no point did he say to the doctor that he vomited at 10pm."

Steve Cram
BBC athletics commentator

Image source, Getty Images

Evan Jager tops this year's rankings and has a real chance to break that Kenyan stranglehold.

It would be phenomenal for the sport as it is an event that a lot of people have shied away from because of the Kenyan dominance.

But Jager has proved that you can run near eight minutes and have the kick at the end to challenge.

He is a bit of a throwback to the all-American kid. He runs really aggressively and was second to Conseslus Kipruto at the Olympics in Rio.

The oddest event in track and field? I think so. And it's up next.

We could see some history too from America’s Olympic silver medallist and world leader Evan Jager. Not since Italy's Francesco Panetta in 1987 has a world or Olympic 3,000m steeplechase title gone to a man born outside Kenya.

Image source, Getty Images

Reigning world champion Shawnacy Barber is out! Three failures at 5.75m and he's on his way home.

He's cleared six metres at his peak.

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

My eyes were scanning all over this field because there was so many contenders.

Eilidh Doyle struggles with the stride pattern sometimes but she managed to make it through.

Allison Curbishley
BBC athletics expert on Radio 5 live

Eilidh Doyle started to waver at hurdle eight. The stride pattern wasn't perfect. She got a bit heavy legged, but so did Dalilah Muhammad.

Five athletes are clear at 5.75m. This one could trundle on late into the night. The men's pole vault was one of the finals of Rio 2016.

Dalilah Muhammad, Olympic champ, is a class above the rest as she cruises to a win ahead of Sage Watson of Canada. Eilidh Doyle runs a good, strong race from lane nine but is third and has to wait for her time.

It's 55.33 - she's into the final!

Image source, Reuters

Team GB captain Eilidh Doyle goes in the third and final semi-final. She came eighth in the Olympics last year and finished sixth in the last Worlds.

Can she reach another final?

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

I was watching Meghan Beesley and she absolutely clattered the eighth hurdle which really slowed her down.

But I think she should be pleased with her performance because she has had a number of tough injuries. If she can get over those she will be amazing.

Image source, PA

Simon O'Brien from the Botswana medical team has now produced an email on air which says that Isaac Makwala was inspected by a doctor on Monday and as a result has to stay away for 48 hours.

The story rumbles on.

Allison Curbishley
BBC athletics expert on Radio 5 live

Unfortunately, Meghan Beesley clattered the eighth barrier. She gathered herself and rallied in the home straight but it was a little too much.

Image source, PA

Ristananna Tracey goes out hard from the gun, it looks like she may have misjudged it but she hands on to win in 54.79.

Lea Sprunger of Switzerland is second and into the final so Sara Slott Petersen is out. Meghan Beesley is seventh and out.