It will be a case of 'catch me if you can' on Friday when Carlin Isles, regarded as rugby's fastest man, looks to inflict more pain on Australia in the Sydney 7s.
The 28-year-old, along with NFL convert Perry Baker, provide the United States with a blistering tag-team of pace that the hosts must counter in their opening game on Australia Day at Allianz Stadium.
USA beat Australia 31-14 in the most recent World Series leg in Durban and have one eye on contending for the World Cup in San Francisco later this year.
Boasting a personal best of 10.13 seconds over 100m, the charismatic Isles was full of confidence at training on Tuesday.
"I'm in real good shape, ready to put the hammer down and tear it up a bit," he said.
"Oh my god yes ... I'm getting better as the years go on."
Isles qualified for the 2016 US Olympic trials with a 10.15 sec 100m, but chose to skip them and focus on his rugby program.
He counts American sprint stars Justin Gatlin and Tyson Gay as close friends and still holds hope of representing his country on both the track and in rugby sevens at the same Olympics.
That's possible, he says, because rugby has only improved his form on the tartan track.
"Rugby has helped my speed honestly, more than it did when I was running track full time," Isles said.
"I ran PBs (personal bests) while training for rugby full time."
Coach Mike Friday likens Isles and Baker - a former wide receiver signed by the Philadelphia Eagles in 2011 - to a pair of race horses with almost too much speed to fit into one team.
"They're exceptional athletes, exceptional personalities and great characters," said Friday, a former England sevens captain, while revealing long-term ambitions to turn Isles into a playmaker.
"Right here right now though, the way I see them operating is as the same but different threats on the outside flanks.
"There's nothing worse than a winger getting tired and looking up and realising they've got the fresh one coming on."
USA and Australia feature in a pool that also includes Scotland and Canada with the Sydney 7s final to be played on Sunday night.
