Great Britain’s Adam Peaty qualified easily for Sunday’s 100m breaststroke final having earlier broken his own world record.
The 21-year-old qualified fastest in 57.62 seconds as he aims to become the first British male to win an individual Olympic swimming gold since 1988.
The City of Derby swimmer’s 57.55 in the heats broke his record of 57.98.
Compatriot Ross Murdoch missed out on a place in the final, finishing sixth in his semi-final.
Peaty, seeking to emulate fellow Englishman Adrian Moorhouse who won breaststroke gold at Seoul ’88, said: “It didn’t really feel like an Olympic semi-final.
“I feel like there’s more in the tank but I want to save myself for that and hopefully cash out tomorrow.
“It is great. It is tough Ross didn’t make it through because it would have been great to have two GB boys through, but I will do my best and show what I am all about.”
Scotland’s Murdoch added: “It was pretty rough, that race. I’ll need to go back and have a think what went wrong. You start slipping water and it costs you.”
Britons miss out on medals
It was a disappointing day for the Britons in the evening’s finals with both James Guy and Hannah Miley missing out on medals after valiant efforts in their respective races.
England’s Guy led the 400m freestyle after the first 250 metres before he ran out of steam and finished sixth.
He told BBC Radio 5 live: “It was trying to go out hard and see how I could go on. Sun Yang [who won silver] and Mack Horton [who won the race] are distance boys so it was going to be hard. I feel like I am in a good place. It is what it is.
“I’ll go back now and chill, watch the Inbetweeners and have some dinner and enjoy tomorrow.
“I am at the Games, I am 20 years old. You move on.”
In the women’s 400m individual medley, Miley, who had competed at Beijing 2008 and London 2012, was in third place during the final freestyle leg before she was touched out of bronze by Spain’s Mireia Belmonte by 15 hundredths of a second.
Hungarian gold medallist Katinka Hosszu set a remarkable new world record in the event.
“I could see [Belmonte]. I knew she was coming back at me but I had nothing left,” said the Scot. “I gave everything I had. It is such a mixture of emotions. I was so close to getting it. It is happy and disappointment all coming together.
“I do this because I enjoy being in the pool. It has been great. I have had a full-time coach since April, so to do all that in such a short space of time with a full-time coach is incredible.”
Max Litchfield, 21, was fourth in the corresponding men’s event on his Games debut.
“It’s fourth, but I was still two seconds behind the guy who was third,” he said.
“It’s not like it was a matter of hundredths of a second. It is a bit annoying.
“But to come fourth in my first Games and to have two personal bests in a day is not too bad.”