There's always a first time for everything, even for Joseph Schooling. He is so focused on his forthcoming National Collegiate Athletic Association (NCAA) races that he has begun to dream about them. Literally.

"Every night, I dream about a different race," he said. "I've never done that before. It just goes to show how locked in I am, how ready I am mentally."

Schooling had a memorable NCAA debut last year, winning the men's 100-yard and 200-yard butterfly in his rookie season.

This time, he is the NCAA top seed for both those events.

The Texas-based athlete said: "It's a good spot for me. If no one can out-seed me, then I think it's going to be very hard for anyone to beat me when I'm rested and I'm focused, and on edge."

Having made history at last year's world championships, where he won a bronze medal in the 100m butterfly - marking Singapore's first podium finish at the meet - the 20-year-old aims to bag the Republic's first Olympic swimming medal in Rio.

"(Competing) last year at the worlds was a huge confidence booster," he said.

"I showed everyone that I can hang with the best in the world. I'm up there and this year, I've become a lot stronger.

"It's a chance for me right now to show the rest of the world that I'm better and I've improved, and I'm ready to compete at the Olympic Games. I'm ready to try to win a medal - an Olympic gold medal."

He feels confident and ready, having set high expectations of himself. "I reached a point where my own personal expectations are higher than what other people expect me to do. The pressure I put on myself outweighs trying to carry Singapore on my back," said the former Anglo-Chinese School (Independent) student.

"I don't really feel the pressure of what other people want me to do because I expect more, naturally. If I meet my own expectations, then obviously I'm going to meet everyone else's."

There is another exciting prospect for him when he touches down in Brazil at the end of July - facing off against legendary American swimmer Michael Phelps, who came out of retirement in 2014.

"It's always a privilege to race Michael," he said. "You always have to step up when you race someone like that.

"For me personally, if I don't have someone racing me or whom I want to beat really badly, it's hard for me to get up and race. With Michael in the field, it gives me a lot more motivation to race and that always makes me do better."

In light of recent doping scandals, Schooling - who was tested three times in the last fortnight - is in favour of increased checks.

"I like seeing Fina (the International Swimming Federation) and Wada (World Anti-Doping Agency) stepping up their efforts to check the athletes. I just hope that they've got their priorities straight and make sure they're testing the right athletes," he said.

Schooling, along with 19-year-old Quah Zheng Wen, has gained automatic qualification for the 100m and 200m butterfly events for Rio.

In addition, he will compete in the 100m freestyle.

But he has not started having regular dreams about Rio yet.