World No. 2 Iga Swiatek was shocked to learn she could receive an automatic move to the top of the rankings after three-time Grand Slam winner Ash Barty made the sudden decision to retire.

The 2020 French Open champion rolled into Miami this week on a hot streak after defeating Maria Sakkari 6-4, 6-1 in the Indian Wells final and winning in Doha in February, and said it had been her goal to chase Barty's spot at the top.

She could get there sooner than expected if the Australian decides to remove herself from the WTA rankings as a result of her retirement.

"It's pretty weird for it to be my goal for two days and it may actually happen that quick. But still it's a longshot because it's her decision," Swiatek said on Wednesday.

"One member of my team (was) knocking and saying, 'Hey, put your laptop down.' I was already scared. Yeah, they said it may be possible that I'm going to be world No. 1," she added.

"When we read all the news, all the rules that may apply, we realized there's no sense to actually think about that right now."

The 25-year-old Barty stunned the tennis world when she announced her retirement on Wednesday, just two months after picking up her third Grand Slam title in Australia.

Swiatek called Barty a model for other athletes to put their own happiness first, but told reporters at the Miami Open that the announcement nonetheless hit her hard.

"I was really emotional, not because of my position, but more because of her retiring at such a young age," said Swiatek.

"I really respect and I really think she's brave that she has made this decision."