By Alan Baldwin

RIO DE JANEIRO (Reuters) - Adam Peaty rooms with James Guy at the Rio Olympics but Britain's big swimming hope clearly pays no attention to his team mate's advice.

Guy, the 200 meters freestyle world champion, recalled on Sunday what he told Peaty before the 21-year-old Briton ripped up his own 100 meters breaststroke world record on his Games debut on Saturday.

"I said 'Peaty, don't smash it, just control it'," he told reporters. "(He said) 'No, I'm going to effing smash it."

"I said 'Fine, mate. Do what you want.' But fair play to Adam, he's a great friend of mine and I'm really pleased for him.

"We're sharing an apartment here so we're always talking, always chatting. I'm really pleased for him, he deserves everything he gets."

Peaty is favorite to become the first British male swimmer to win an Olympic gold since Adrian Moorhouse in 1988 when he swims on Sunday night.

On Saturday, he set a world record of 57.55 seconds in his very first Olympic race -- a time 0.37 quicker than his previous best -- and almost went faster again in the evening.

Guy, who came sixth in his opening 400 freestyle race on Saturday, would not divulge what further advice he might have given his friend.

The two world champions are part of a British team that has been growing in stature but Guy said Peaty was still in a different league.

It's nice to look up to someone really," he said. "We're both a similar age but he's way up there and someone to look up to and aspire to, to see what he does and how he prepares himself for a race."

As far as his own performance was concerned, Guy said he felt more composed than he had on the opening day -- when he had led the 400 before fading over the last 100 meters.

"I feel like I'm in the meet now," he said after setting the fifth equal fastest time in the opening 200m heats with Townley Haas of the United States.

"Just there, I felt so much more controlled instead of trying to kind of blast the 400, I just felt like I was in my element there.

"It's just an emotional thing really. Yesterday I was bit upset coming sixth, but you've got to get over it. Today's a new day. Yesterday is done and buried now, I've moved on."

(Reporting by Alan Baldwin, editing by Rex Gowar)