ROME, ITALY - After a dominating 43.91 performance at last weekend's Meeting Gaz de France in Paris, World 400m champion Jeremy Wariner appeared untouchable on his road to a slice of the $1 million IAAF Golden League Jackpot. But after Xavier Carter stunned the athletics world with his 19.63 victory in the Lausanne 200 two days ago, Wariner might actually have an unanticipated challenge when the pair line up for the 400m Friday night at the Borotalco Golden Gala - IAAF Golden League in Rome's Stadio Olimpico. And both are looking forward to their match-up.

"I really want to see what I can run going against Jeremy," said Carter, more affectionately known as 'The X-Man'. "I really never have run just the 400 and that's it; I've been running races and then the 400. I really want to see what I can run running fresh."

In June, the 20-year-old became the first to ever claim both the 100 and 400m NCAA titles, a combination previously thought to be virtually impossible at that level. Adding a pair of relay titles to his victory haul, Carter produced a quadruple win that hadn't been witnessed at the NCAAs since the days of the legendary Jesse Owens.

Carter took a month off from competition after the NCAAs, doing little but resting for about a week before resuming with some light training -- "basically just some strength training," he said-- prior to his professional debut in Luzern on July 6, where he won the 100 in a near-PB 10.11. Obviously still in fine condition, he said he was a expecting a PB in the Lausanne 200, his first half-lap effort since April. But when the clock eventually flashed 19.63, Carter, like most others, was shocked.

"I wasn't sure what kind of time I'd be able to run, but I knew it would a good time because I've been training for the 400," he said. 'I knew I'd run a PR. But it was a shock. I'm shocked still. Running the second fastest time ever, I feel like it's a big accomplishment." Carter, at just 20, trails only world record holder Michael Johnson's legendary 19.32 in the all-time 200m standings.

Wariner, who's improved his 200 PB dramatically this year, was impressed as well.

"I watched him at the NCAAs and saw him win the 100 and come back and win the 400. That's impressive. And his 200 in Lausanne was impressive," said Wariner, the World and Olympic champion. "With the right people pushing him, there's no telling how fast he can go, and with the right people pushing me there's no telling what I can do. With us pushing each other for the rest of our careers, we might even be able to run into the 42s for the first time."

Of his dash into the history books in Lausanne, Carter said that he largely ran the race he was expected to run.

"I knew I was going to be strong at the end because of all my speed work. I made a little mistake on the curve --I think I relaxed a little too much-- but other than that it was a great race."

Like Wariner, Carter is relishing his Rome appearance, certainly the toughest test of his young professional career.

"I'm not going to say I can't beat him or if I can beat him. But it is going to be a challenge. I'm not going into the race to not challenge him. I'm a competitor, and whoever the man is at the time, I'm trying to shoot for him. He's a great athlete and I respect him for that."

Carter said that with his limited experience of contesting the full lap with a fresh pair of legs, he has no idea what his limit in the event might be, and doesn't really know what kind of performance to expect tomorrow night.

"I don't really have a time in mind. Maybe low 44. Maybe 43."

But he did make just one prediction.

"It's going to be a special race. I'd tell everyone to keep their eyes open for it."