South African team MTN-Qhubeka are smarting themselves after it was discovered that one of its top riders Adrien Niyonshuti will miss most of the season with an illness.The Rwandan rider, the first black to race in the Mountain Bike category at the 2012 Olympics, was recently diagnosed with deep vein thrombosis (DVT). DVT is a blood clot in a deep vein, normally in the legs. The 27-year old’s right calf was swollen after a mid-January flight. The clot travelled through his body and into one of his lungs, where it became a pulmonary embolism essentially an arterial blood clot in the lungs that can, in severe cases, stop blood flow and eventually cause death, doctors say.Team Qhubeka reported that symptoms of the DVT occurred after an international flight, and his doctors believe that prolonged inactivity, exacerbated by mild dehydration, is the likely cause.On his return from Rwanda in mid-January, Niyonshuti reported mild swelling of his right calf. Investigations confirmed a DVT complicated by pulmonary emboli. He was immediately admitted to hospital under specialist care.DisappointedNiyonshuti has since been discharged and is feeling well. However, he will need a prolonged course of anticoagulant (blood thinning) treatment and will not be able to participate in any contact sport for a considerable period. He will be out of competition indefinitely.Dr Jon Patrios, MTN-Qhubeka Team Doctor said, "In a situation like this, the immediate and long-term health of the athlete takes absolute precedence over the disappointment associated with the team losing one of our high profile riders.”After coming to terms with the news, Niyonshuti said, "I am disappointed but grateful that this was discovered sooner rather than later. I was looking forward to testing myself against some of the biggest riders in the world. "I will use this time to rest and reflect on my career and what I’ve achieved so far. I will be able to start indoor training in a couple of weeks and we’ll continue closely monitoring my health and progress,” Niyonshuti added.Transition jeopardised"This is a sad day for the team as we know Niyonshuti’s potential and we know how badly he wants to make the transition to the road cycling discipline and race in the world’s biggest races,” Team principal, Douglas Ryder added."We believe things happen for a reason and this is an opportunity for Niyonshuti to inspire Qhubeka bike recipients in communities to become professional cyclists telling his stories of working hard to become an Olympian. After riding for the Rwanda national cycling team, Niyonshuti secured a professional contract with Team MTN Energade, beginning in the 2009 professional season.