World number one Kaylee McKeown of Australia will be withdrawing from the women's 200 metres medley in the upcoming Tokyo Olympics to focus on her backstroke events, the national team coach said on Thursday, citing a tough schedule.

McKeown, 20, is ranked number one in three events coming into the Tokyo competition but the medley would have been in conflict with the 100m backstroke, for which a strong challenge is expected, head coach Rohan Taylor said.

Taylor said it was a huge decision.

"Absolutely it is. But, you know, you got a rookie coming in and the Olympics, it's going to be a big experience for her, it's a big call," he told reporters.


"They've gone for months talking about it and I respect that decision, they're going to focus on the backstrokes and medley relay."

The withdrawal could be a blow to Australia's hopes of taking on the United States in the pool. The Queenslander was a highlight of the Australian Olympic trials last month, setting a world record in the 100 metres backstroke and strong performances in both the 200m backstroke and 200m medley.

The swimming competition gets underway on Saturday.

She had made the decision with her coach and would have a chance to take on more events at other Games, Taylor said.

"She's never done it before," he said of the Olympics.

"So it's new to her, and I think emotionally, we need to respect that but if it's something she's not familiar with, but then in the future we need to make sure she's familiar with it because she is such a weapon in so many different facets."