Dwain Chambers has heaped the pressure on UK Athletics with a dominant 60m victory at the world indoor trials and national championships.
Chambers ran a season's best 6.55 seconds to win the title
The 29-year-old's win guarantees him a place in the British squad for next month's World Indoor Championships under UKA's selection policy.
But UKA had made it clear it does not want Chambers, who served a two-year drugs ban, representing Britain.
The selectors meet on Monday and are likely to announce the team on Tuesday.
Olympic silver medallist Steve Cram revealed he would not pick Chambers to represent Britain, and believed the two-year ban the sprinter had received was not enough.
"If I personally was a selector then, no, I wouldn't pick Dwain Chambers to represent Britain in the 60m at the World Indoor Championships," Cram wrote in his BBC Sport website column.
"The reasons? He did an awful lot of damage to the sport in the UK and in world terms too; and as an athlete it's not as easy to be quite as forgiving as the general public might be.
"I don't think a two-year ban is ever enough punishment, and I'm saying that for all drugs cheats, not just Dwain. It just shouldn't be that easy to come back."
BBC 5 Live athletics correspondent Mike Costello said Chambers had made it very difficult for UKA not to pick him.
"I think you'd have to suppose that UKA will pick him now - after all, they did two years ago when he first came back," said Costello.
I just hope the selectors do the right thing
"In Sheffield, it was hard to find someone who was really angry with Chambers for what he's done - and the fact that competing athletes are not coming out against him is giving him some momentum.
"UK Athletics are trying to change their stance on this, but they have already selected him and that weakens their position."
UKA had wanted to stop Chambers running because he has not been in its drugs testing programme since 2006.
But it had to let him run after admitting it did not "sufficiently strong legal grounds" to stop him.
Chambers pressed home his claims by powering away from the field in Sheffield to win in 6.55 seconds - the fastest time in Britain in 2008.
The Londoner felt his victory should justify his selection, telling BBC Sport: "Hopefully I will have done enough to get to the Worlds.
"I'd like to believe my performance warrants that and I just hope the selectors do the right thing.
"Today has been worth everything I've been through; and it's not over yet as my goal is to win the World Indoors."
However, the selectors could choose to invoke their "exceptional circumstances" ruling to deny him a place in the British team.
They could argue that because Chambers is not eligible to compete in the Olympics, after serving a two-year drugs ban, it is not in their interest to select him for any competition in an Olympic year.
UKA chief executive officer Niels de Vos has taken a strong line on the Chambers issue but insisted the sprinter would not be singled out for special treatment.
De Vos told BBC Sport: "I'm not on the selection panel but he will be treated the same as any other athlete who has raced at these events.
Asked whether Chambers should be selected, De Vos added: "I've already made my personal opinion clear, now it's a matter for the selectors.
"We've consulted with our lawyers and checked our rules. It would be wrong to change those retrospectively, but in the future we have to make sure that there are no grey areas."
UKA had been reluctant to let Chambers run because it wants to take a hard line on athletes returning following drugs offences.
Chambers tested positive for the steroid THG in 2003 and served a two-year ban, but returned to the sport in 2006.
Dwain has done his time and I have no problem with him running
The Londoner then chose to pursue a career in American football at which point UKA, believing he had retired, took him off UK Sport's drug-testing list.
UKA agreed to accept Chambers could compete in Sheffield under IAAF rules as he had constantly informed the athletics' governing body of his whereabouts.
Chambers's second comeback to the sport has had a mixed response from the public and athletics fraternity.
However, the announcement of Chambers' name in Sheffield was greeted by widespread cheers and there were scattered shouts of 'Go on Dwain'.
He added: "Drugs are wrong and I feel I have served my time and shown that I can come back and win races as clean so I feel I am a good example to people.
"A lot of things have been said and maybe the media have put me under pressure but the support I have received from the public here was fantastic.
"I kept my cool on the track and came out first so I am happy with that.
"The support of everyone here meant a lot. I acknowledge I have made a mistake in the past and I want to move on with my life and enjoy running again."
Simeon Williamson, who finished second, said he did not have a problem with Chambers, his training partner, taking part in the event.
"Dwain has done his time and I have no problem with him running," he said.
"There was extra pressure in the race with him involved and I am pleased to finish second and hope to go to the World Indoors now."