Chris O'Hare is in the mix at the bell.

Steve Cram
BBC athletics commentator on BBC TV

Chris O'Hare has called himself a terrier. He will be in the right position, but does he have the pace to go through here? 

That first semi-final was slow so the second lot have gone off quickly. They are eyeing those two fastest losers spots are very much up for grabs. 

Can we get a second Brit into the 1500m final? Chris O'Hare goes in semi-final number two. Ronald Kwemoi, second fastest in the year this world, is also in.

Top five go through again...

BBC One

Charlie Grice: "I am so happy to get through. When the pace was slow I was quite nervous but I knew my 800m speed was good. I told myself to stay patient and I am glad I redeemed myself because Tuesday was not me. A few times people were cutting in, so I am just glad I stayed on my feet. I wanted to make sure I proved myself today. It was close but I am thrilled. Two days to rest up and the final will be a cracker.

Brendan Foster
Olympic medallist and BBC athletics commentator on BBC One

Charlie Grice got his first break on the back straight. There was no shortage of talent around him but there was a determination in Charlie. He saw his chance. 

Image source, Getty Images

No British involvement in another final tonight, but the female javelin throwers get their chance for a shot at history.

Maria Andrejczyk of Poand leads the world this year with a throw of 67.11m - that's the wingspan of a jumbo jet - while defending champion Barbora Spotakova is not far behind.

Jade Jones is defending her taekwondo -57kg category title in around 75 minutes time.

The Welsh fighter is up against Spain's Eva Calvez Gomez at 02:00 BST.

Gomez is ranked second in the world. Behind? Jones.

Jamaica's O'Dayne Richards looks like he's going up for a corner rather than hurling a heavy shot put through the air.

But hurl it he has and he's currently in fifth place with a best of 20.64m.

Image source, Reuters

Steve Cram
BBC athletics commentator on BBC TV

Well done Charlie. He may have been fortunate to make it through but he did not panic at the bell. He is into the Olympic final. Huge relief and a huge achievement.

Well ran Charlie Grice! He spots a tiny gap on the blindside, the inside, and goes for it, hanging on strongly to take fifth place and a place in the final. He's delighted with that! The race was won by Asbel Kiprop. Who showed an extraordinary turn of pace to go from last to first in the space of about 60m. 

Still slow, still bunched up. Sprint finish on the cards. 

Ray Bradnock: I think Daley Thompson could still give the decathletes a run for their money after a couple of weeks training  

Brendan Foster
Olympic medallist and BBC athletics commentator on BBC One

I am very nervous. This is a tough qualification. Only five go through and the first lap has been pretty pedestrian. A faster race will suit Charlie Grice.

Slow pace to start this race off. If you saw Laura Muir in the 1500m last night you'll know how tactical these races can be. The first 400m takes the field 63 seconds. 

Steve Cram
BBC athletics commentator on BBC TV

This will not be easy for Charlie Grice or Chris O'Hare. Charlie goes up first. He was fading badly in his heat and perhaps a little fortunate to advance.

Action on the track now - Charlie Grice is in the first semi-final with the top five certain to go through. Asbel Kiprop - fastest in the world this year - is in this race too.

Denise Lewis
Olympic heptathlon gold medallist on BBC TV

I don't think anything can stop Ashton Eaton in this one. If he has to run for it he really will, but let's not jinx him. However, gone are the days when you could see Daley Thompson cruise around. This is a proper race.

Maggie: Wondering how many selfies Usain Bolt might take on the back straight?