Yokohama - Jamaica's Shelly-Ann Fraser-Pryce has called on the country's track athletes to step up at next year's Tokyo Olympics - the first since sprint king Usain Bolt hung up his spikes.

The two-time Olympic 100m champ, competing at this weekend's world relays in Yokohama after returning from maternity leave, predicted a bright future for Jamaican sprinting after Bolt bowed out in 2017 with eight Olympic gold medals and 11 world titles.

"It's a totally different feeling without Usain," Fraser-Pryce told AFP.

"But as anything, with time things change. We have a lot of young athletes here and this is a time for them to create a name for themselves.

"I don't think any athlete should try and pressure themselves to fill Usain's shoes," added the 32-year-old.

"What he did was remarkable for the sport, so for us it's just a case of trying to do our best."

Jamaica's male sprinters struggled at last year's Commonwealth Games, where Yohan Blake trailed in third in the 100 metres and the men's 4x100m relay team settled for bronze behind England and South Africa.

Trinidad and Tobago's Michelle-Lee Ahye also pipped Jamaica's Christania Williams to gold in the women's 100m on the Gold Coast, while England beat the Jamaicans in the 4x100m.

But Fraser-Pryce, who captured back-to-back 100m Olympic titles at the 2008 Beijing and 2012 London Games, backed her fellow Jamaicans to hit back in the run-up to the 2020 Tokyo Games.

"It's not about Usain, he's not here," said the seven-time world champion. "Yes he left a legacy that I don't think anyone will match for a very long time. But we have it to look to as inspiration. I think it's going to be a beautiful transition for Jamaica."

Fraser-Pryce, whose bid for an Olympic 100m hat-trick ended in bronze at the 2016 Rio Olympics, admits to sleepless nights being away from her baby son Zyon, born in August 2017.

"In Jamaica we're about 15 hours behind so I got up at three this morning just to FaceTime," she said.

"It's still a surreal moment for me because as a mum I would love to bond with my son every day. But you don't get that chance as an athlete. It's very hard to be away."

Fraser-Pryce goes in the women's 4x200m in Yokohama on Sunday - Mother's Day, a date not lost on her.

"When I heard I would be missing my son on Mother's Day... the sacrifices you make sometimes it makes you want to cry," she said. 

"But it comes with the territory and competing with such a strong team gives me motivation."

Fraser-Pryce is set to run the third leg alongside Elaine Thompson, Shericka Jackson and Stephenie Ann McPherson.

"I've never run a 4x200 before so I'm depending on the first two ladies to get off to a good start," said Fraser-Pryce, who bagged an individual silver medal in the 200m at the London Olympics.

"But I don't usually have nerves when it comes to the relays - I'm just more focused on getting the stick around. If we have that solid first leg, we will have less pressure so we can relax and run as fast as we can."