Will Perrett is prepared for a battle against the odds in his quest to be part of next summer's Great Britain's Olympic squad.

Perrett will be back at the Lee Valley Velodrome this weekend for the final two rounds of the UCI Track Champions League, 11 months after a stunning victory in the men's scratch race here helped him force his way on to Britain's podium programme.

At the time, Perrett had quit his job and was self-funding in a bid to prove himself to the national team coaches, and his Champions League display came after he had taken a points race fifth on his World Championships debut and won the British Madison title alongside Mark Stewart.

It worked and in January he was invited in to train full-time as part of the elite programme.

But nothing has come easily for Perrett and a fresh setback was just ahead. In March he was diagnosed with glandular fever as a result of the Epstein-Barr virus.

"Initially I was just incredibly ill," Perrett told the PA news agency. "I had tonsillitis-esque symptoms and incredible fatigue. I'd go for a walk around the block, come back and sleep for an hour. It was horrible. You feel a bit helpless."

Had it happened while Perrett was funding himself, the illness could have ended his elite racing career.

"I would have been absolutely screwed," he said. "If I'd not been on the programme I wouldn't have been able to race, I wouldn't even have been able to work because I was so tired. It could have ended everything.

"That's a massive benefit of being on the programme. You get so much help from the doctors, the coaches. They've not been pushy. They've said, 'Look, we need to rebuild your foundations and then build you back up.' That's what I'm hoping to do this winter."

Perrett believes he is still missing around five per cent of his threshold – a massive number at the elite end.

Yet he was able to claim another fifth place in the points race at the World Championships in Glasgow and earn another invitation to the Champions League, the glitzy made-for-television series which is in its third season.

Perrett struggled for results in the opening three rounds in Mallorca, Berlin and Paris as he works his way back up to speed, but will come to London for the sold-out finale on Friday and Saturday buoyed by memories of last December.

"I've been a bit ropey after a bit of time off after the worlds but I've loved being back (in the Champions League)," he said. "It's good fun, the racing and the atmosphere."

There will be plenty of British interest in London, with defending champion Katie Archibald top of the women's endurance standings, Emma Finucane third in the women's sprint, and Will Tidball and Stewart fourth and fifth respectively in the men's endurance.

Perrett's goal is to keep plugging away for form as he eyes selection for the Euros in January. He remains an outsider for Paris as only four male endurance riders will go, meaning those four must be competitive in the team pursuit, but a chance is all he asks for.

"At the moment I haven't got the results or the experience at that level of team pursuiting," he said. "Only four riders go to the Olympics. It's a crazy stupid rule. The Madison is a 200-lap, 50 minute event but to get into that you have to be able to get into the one that lasts three minutes 45 seconds.

"It's a stupid rule but it's the one you have to aim towards…But I have an opportunity and as long as I get the opportunity, that's what matters."