A US federal court in Gatlin's hometown of Pensacola, Florida [Images], held a one-day hearing on a request for a preliminary injunction that would allow the 26-year-old Gatlin to take part in the trials in Eugene, Oregon.

The track meeting begins on Friday with the first two rounds of the 100 meters scheduled for Saturday.

US District Judge Lacey Collier said he would deliver a prompt ruling but gave no time frame.

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Lawyers for athletics organizations argued that Gatlin could appeal an arbitration decision suspending him only at the Swiss Federal Tribunal.

"This court simply doesn't have jurisdiction to vacate that award," said Howard Jacobs, a lawyer for the US Olympic Committee. "Even if it did [grant the motion] the International Olympic Committee won't let him compete if he qualifies."

Collier issued a 10-day restraining order on Friday prohibiting the US Anti-Doping Agency (USADA), US Olympic Committee (USOC), USA Track & Field and the International Association of Athletics Federations from barring Gatlin from the trials because of his doping suspension.

The four organizations opposed Gatlin's request at Monday's hearing and Lorence Bielby, a USOC attorney, said it would appeal against any ruling by the judge in the sprinter's favour.

Gatlin, who attended the hearing dressed in a brown suit and was accompanied by family members, was suspended for four years after testing positive in 2006 for the male sex hormone testosterone.

It was considered a second doping violation as the sprinter also tested positive in 2001 for amphetamines that were part of a medication to treat Attention Deficit Disorder.

He alleged in a lawsuit against the four organisations that the Americans with Disabilities Act was violated when an arbitration panel used the first positive test to increase his penalty for the 2006 offence.

"We are dealing with a discrimination. They are here today, we contend, to further discrimination based on disability, which is contrary to the Olympic charter," said Joseph Zarzaur, Gatlin's lawyer, referring to the four organisations.

NO JURISDICTION

Court argument centered on the issue of jurisdiction and the gravity of Gatlin's 2001 offence and judge Collier at times appeared unimpressed by lawyers opposed to the sprinter.

"I am troubled when the argument is ... that we will impose the process regardless of the fairness just because it is our system," Collier told lawyers opposing Gatlin's case. "You ought to be embarrassed by what you have done in this case up to this point."

But William Bock, an attorney for USADA, said Gatlin did not contest his suspension at the time. He quoted a letter from the sprinter in which he acknowledged that if he committed a second violation he could receive a lifetime ban.

The Court of Arbitration for Sports rejected an appeal from Gatlin this month after he asked the independent Lausanne-based body not to consider the 2001 ban in determining his suspension for the latter offence.

Gatlin could have been suspended for two years only had the positive test for testosterone been considered his first and would have been eligible to compete in the Olympic trials.

Gatlin won gold in the 100 meters at the 2004 Athens Olympics [Images], silver in the 4x100 relay and bronze in the 200. A year later he won the 100-200 double at the Helsinki world championships.

In 2006, he equalled the 100 meters world record time of 9.77 seconds set by Asafa Powell [Images] of Jamaica. The record has since been broken by another Jamaican Usain Bolt.