LONDON (AP) – Justin Gatlin’s coach could face a two-year ban if the Olympic and world champion sprinter is found guilty of a second doping violation, the sport’s international governing body said Monday.

“Once we have enough evidence to prove it, then we have the power to prosecute him,” IAAF spokesman Nick Davies said, referring to Trevor Graham.

The International Association of Athletics Federations will only act should evidence link Graham to any doping violations and the U.S. Anti-Doping Agency decides not to take action against him, Davies said.

While USADA does not normally go after coaches, the U.S. Olympic Committee is looking into ways to hold them responsible if they’re involved in doping cases.

Among the considerations would be banning them from training facilities and denying access to the Olympics and other major events.

While not referring to Graham or Gatlin specifically, USOC spokesman Darryl Seibel said Monday that the federation has long been looking into ways to penalize coaches if they play a role in doping.

Seibel said the USOC would never back down on its stance that athletes are ultimately responsible for what goes into their bodies.

“That said, we believe there are others who carry significant influence with athletes who must also share in the responsibility for clean competition,” Seibel said. “Specifically, agents, coaches and trainers must also be held accountable when there is a pattern of doping positives.”

Graham did not return phone messages seeking comment and no one answered the door at his house in an upscale neighborhood of Raleigh, N.C.

However, his attorney, Joe Zeszotarski, also of Raleigh, told The Associated Press in an e-mail that his client has never taken part in distributing illegal substances to athletes.

“It is curious that people who are not familiar with the situation can claim that Trevor has somehow done something wrong,” Zeszotarski wrote. “It is worth reminding everyone that one of the chief reasons the issue of doping has come to the forefront is because of Trevor’s integrity and courage in turning in the sample that led (to) the uncovering of the BALCO enterprise. Given what some people have lost as a result of Trevor’s integrity in turning in the sample, it is not surprising that there are people who would make false claims about him.”

Published reports have identified Graham as the coach who sent USADA a syringe containing the designer steroid THG, which until then had been undetectable.

A man who worked with Graham told a San Francisco grand jury and investigators that he supplied performance-enhancing drugs to the coach and many of his athletes, including Marion Jones, Tim Montgomery, C.J. Hunter and Michelle Collins, the New York Times reported last week.

At least six athletes who trained under Graham have received doping suspensions. Graham, however, has always denied direct knowledge or involvement with drug use.

Meantime, Gatlin’s mother, Janet, said during a telephone interview that her son was staying at the family’s Pensacola, Fla., home and was “doing as well as can be expected.”

Gatlin said Saturday he had been informed by the USADA that he tested positive for testosterone or other steroids after a relay race in Kansas in April. He said he has never knowingly taken banned substances.

If found guilty, Gatlin would face a life ban and the loss of the world 100-meter record. He equaled Jamaican Asafa Powell’s mark of 9.77 seconds in May, a month after the positive test. Gatlin would keep his Athens gold medal in the 100 and world 100 and 200 titles from 2005.

Gatlin was suspended in 2001 after testing positive for an amphetamine found in medication he was taking for attention deficit disorder. The IAAF gave him early reinstatement, but said the suspension remained on his record and he would face a life ban for any second violation.

The IAAF said it gave little credence to Graham’s claim that Gatlin was the victim of a massage therapist who rubbed testosterone cream on his legs without his knowledge.

“We have a strict liability rule that what’s in your body is your responsibility, so unless there was an independent witness who saw everything clearly there really isn’t a possibility that there would be something in that,” Davies said.

Cameron Myler, Gatlin’s attorney, said Graham was “not speaking on behalf of Justin.”

Speaking by telephone from her office in New York, Myler said Gatlin has voluntarily withdrawn from competition until the doping issue was resolved.

She said her client’s case would be based “on the exceptional circumstances clause of the World Anti-Doping code.”

That clause allows for a lesser penalty if it can be proved that the athlete was not responsible for the positive test. The exception is rarely granted.

“It’s a difficult standard, but it’s definitely something that we’re working toward,” Myler said.

“We’re trying to reconstruct what happened in Kansas, looking at who had access to Justin to cause the positive result. Justin didn’t do anything to cause this and he didn’t authorize anyone to put anything on him that would have caused it.”