Justin Gatlin believes American sprinters are ready to prove themselves as the fastest men in the world after Usain Bolt's retirement.

With Jamaican showman Bolt now off the scene, the 100 metres and 200m risk losing some of their lustre, but Gatlin sees an emerging generation of track stars jostling to take over at the top.

Americans account for four of the five fastest times over 100m this season and three of the four quickest in the 200m.

Christian Coleman, 23, owns the season-leading best time of 9.81 seconds in the shorter sprint, with fellow Americans Noah Lyles and Gatlin also dipping under 9.90secs.

The little-known Cravon Gillespie clocked 9.93 in Austin last month for a personal best too.

Doha will stage the IAAF World Championships later this year, and 37-year-old Gatlin will bid to defend his 100m title on the evening of September 28.

Asked whether USA can be the dominant sprinting nation, after years of Jamaican success, Gatlin told Omnisport: "I think so. It just takes a lot of the youth and the young athletes coming up and looking at what we have done in the past and having pride.

"[It's about] wanting that success and training themselves very hard to make Olympic teams, World Championship teams ... and I think it's on the rise from both sides, both the men and the women."

Bolt's last individual 100m race came at the 2017 World Championships in London, when the eight-time Olympic gold medallist could only finish third as Gatlin took the glory.

It was an unpopular victory for many, not least because Gatlin has served two doping bans, but Bolt notably jumped to his defence.

The post-Bolt era has yet to see any athlete threaten his world record of 9.58secs in the 100m, but Gatlin suspects a heightened competition for medals should again make the race unmissable in Qatar.

 
 
 
 
 
 
 
 
 
 
 
 
 

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Assessing likely rivals, Gatlin said: "If we're looking at it right now, obviously potentially Christian Coleman, Noah Lyles, a lot of other young runners. I always give respect to the other runners that are going to be out there because a star is born at any moment.

"Anybody has an opportunity to put together a great race, and it might be their moment in 2019 in Doha to have the best race of their life.

"Guys are still running elite times. It's about the direction they're coming from. Usually you have one guy you can focus on, which was Usain, who was running fast times and you could focus on that.

"But now you've got Noah Lyles, Christian Coleman, anybody that's running fast times. So you always have to stay on guard and be ready for whoever's going to run fast and you have to be ready to run faster."