Some big names still to come. Phelps? Lochte?

You bet. 

18 year old Australian Kyle Chalmers takes gold, breaking the junior world record in the process.

GB's Duncan Scott swims a very credible fifth.

Taylor McKeown wins it, Molly Renshaw touches in to take second in a new British record! Fine swim. Well paced, strong and long.

GB have two in the final. Confirmed. Molly Renshaw and Chloe Tutton both in. 

Taylor McKeown of Australia is ahead after 100m, Molly Renshaw second. World record holder Rikke Moller Pedersen between them. Strong last 50 ahead...

100m champ Lilly King leads after 50m. Molly Renshaw well in the mix. 

Will we have none, one, or two Brits in the final? Away in semi number two and Molly Renshaw is up amongst it after 50m. 

Chloe Tutton after coming third in her heat tells BBC One: "I am really pleased with how I swam. I'm not going to get sucked into what Efimova has, I just want to get on with my plan.

"It's nice to have two Brits doing well at the moment."

Outspoken Lilly King, 100m champ, takes a wrong turn as she walks out and goes to lane one, not eight. This second semi is packed with quality. 

Semi-final two

1 Kanako Watanabe Japan

2 Shi Jinglin China

3 Molly Renshaw Great Britain

4 Rikke Møller Pedersen Denmark

5 Taylor McKeown Australia

6 Viktoriya Zeynep Güneş Turkey

7 Jessica Vall Spain

8 Lilly King United States 

Phew! And it is Spain's Mireia Belmonte who hangs in there for gold, beating Australia's Madeline Groves by just three hundredths of a second. It is a historic gold too as it is Spain's first in the pool.

That should be enough for Chloe Tutton to make the final but we have to wait and she. She clocked a time of 2.22.71.

GB's Duncan Scott after coming fifth: "I am delighted with that. I was happy to make the semi-final and to be in that final was incredible. Hopefully things can move on next year.

"Everyone in the GB team is swimming with confidence at the moment. We have the best breaststroker ever and the whole team wants to keep swimming."

You can catch up with all of tonight's action in diving, swimming, football, kayak slalom and table tennis on the BBC Sport website.

Click here to watch the best of tonight's action in our Rio 2016 Playlist

Rie Kaneto comes through to win the semi, Yulia Efimova second and Chloe Tutton a tight third behind. A great swim. 

Andy Jameson
BBC commentator and former British Olympic swimmer

It's brave from Tutton but it looks comfortable. And she has a great second half.

Chloe Tutton still leads at 150m but the pack are circling...

At 100m it's Chloe Tutton who leads the field by more than half a second. Yulia Efimova is nowhere - she's left herself an awful lot of work. 

Yulia Efimova was very slow in the first 100 of her heat and she is doing the same, the tortoise and the hare?

Chloe Tutton is the other way, ahead at 50m. Fast. 

Yulia Efimova, controversial Russian athlete, steals the attention as the athletes line up on the blocks. Shocking pink, on the outside of Chloe Tutton.

Away they go...

This is the Brazil we all know! 

Beautiful football sees them carve up Denmark as Neymar lifts a smart ball for Douglas Santos and his cutback is smashed in by Luan.

They've got their mojo back, and I reckon there's more goals in this.