Former Tour de France King of the Mountains Michael Rasmussen is facing a serious setback to his return to pro cycling after being diagnosed with mononucleosis.

The illness is associated with debilitating fatigue and explains the slump inform that Rasmussen recently experienced. He dropped out of the Settimana Lombardia after placing only 119th in the uphill prologue, losing a very considerable two minutes and 32 seconds to the stage winner Michele Scarponi (Androni Giocattoli). His form has been decidedly average for much of the season.

“On the one hand, it is of course deeply frustrating to be sidelined at a time when I face some of the most important tasks in the spring,” the Miche rider said, speaking to Politiken.dk. “On the other, it is nevertheless reassuring to have a clear message about what is wrong. Now there’s nothing else to do but to wait until I get well before racing again. It is impossible to say at the moment when that will be.”

Rasmussen is currently able to exercise, but not at a high level. “I continue to train, but cannot push myself to the limit. Yet I feel it is important that I keep myself going, so I’m not handicapped any more than necessary when I get the green light to start again.

“No one has yet been able to tell me when that will be. It is very depressing to be absolutely powerless and watch the events just going past my nose.”

The Dane is one of cycling’s most controversial characters, being thrown off the 2007 Tour de France when just days away from an almost certain victory. He had lied about his whereabouts prior to the start of the race, claiming to be in Mexico when he was really in Italy, and was thus not available to be tested in out of competition doping controls.

He claimed he was the victim of a witchhunt, but also faced allegations during the race that he had once tried to get another cyclist to unwittingly transport doping products for him. In addition to that, the French national anti-doping laboratory LNDD said after the race that there were indications that he had used Dynepo during the race.

The product is a type of EPO but Rasmussen could not be sanctioned due to a loophole in WADA’s rules. He however served a two year suspension for missing anti-doping tests.

The 35 year old recently made more headlines when he told Weekendavisen that he wished death on some of his critics.

“It’s guaranteed that if some people died, I would live a happier life,” he said, in a bitter outburst. “If they suffered a lot and then died, even better. It may be a sick idea to have and perhaps even more sick to say out loud, but it is the truth. There are some people that if something really bad happened to them, I will immediately send a card, and my congratulations.”

He later backtracked on the remarks, which did his public image little favours.