Justin Gatlin, reigning world champion in the 100m sprint, intends to pull out all the stops in Saturday's race at the 2018 Shanghai Diamond League athletics competition.

"I want to get a world-leading time in Shanghai. I ran at the Grenada Invitational earlier this year and the track was a little slower, but the track here is a little faster and harder, so I want to be able to get the job done and put away a strong competition," the 36-year-old said at Thursday's pre-competition media event at Qibao Middle School, where he met with student athletes.

"There are going to be Chinese and Japanese athletes in the race on Saturday and they are good contenders. I think this is going to be one of the best races of the year so far," he added.

One of the Chinese athletes Gatlin will be up against is local favorite Su Bingtian, who won the 100m at last year's Diamond League meet in Shanghai.

Su has enjoyed a blistering start to the 2018 season, winning the 60m final at the IAAF World Indoor Tour in Karlsruhe, Germany, in February and setting an Asian record of 6.47 seconds in the process. He eclipsed it with a time of 6.43 just a few days later at the tour's next stop in Dusseldorf.

The 28-year-old also made history in March when he won silver in the same event at the World Indoor Championships in Birmingham, England, becoming the first Chinese male sprinter to medal in an individual event at an international competition.

Earlier this month, Su cruised to a comfortable victory in the 100m at the Hong Kong championships with a modest time of 10.28sec.

Gatlin, who spoiled Usain Bolt's farewell party last year by beating the Jamaican legend for the 100m title at the world championships in London, said he is well aware of Su's exploits.

"I'm definitely going to have to take him seriously. Su is a strong athlete who won silver at the indoor championships, so he's going to be a great opponent," Gatlin said.

"I'm going to have to take him seriously. When the gun goes off I'm going to be watching out for him."

Up-and-coming US sprinter Christian Coleman, who finished second to Gatlin in London, was scheduled to compete here but pulled out earlier this week, with his coach saying the move was "precautionary".

Coleman has also had an impressive start to the season, setting a world record at the indoor championships in Birmingham.

When asked if Coleman's withdrawal was good news for the rest of the field, Gatlin disagreed, instead expressing concern for his compatriot, whom he raced alongside in the 4x100 at the Tennessee Relays in Knoxville in April.

"It's never good news. He might have injuries and you never want to wish that on any athlete because of how hard we all work," Gatlin said.

"We're from the same college, so I want to see him come back strong and be good for the rest of the season."

Also scheduled to compete in Saturday's 100m is Canada's Andre De Grasse, who won the silver medal in the 200m and bronze in both the 100m and 4X100 relay at the 2016 Summer Olympics in Rio de Janeiro.

De Grasse made his comeback at the Drake Relays at the end of April after recovering from a right hamstring injury.