The Guardian newspaper and websites around the world are reporting that Damon is getting into shape for a role as Lance Armstrong.
The biopic will be based on Armstrong's autobiography, It's Not About the Bike: My Journey Back to Life and produced by Frank Marshall, producer of one of 2004's top films, The Bourne Supremacy, starring Matt Damon.
Damon will be put through a punishing training regime to play the cancer survivor and cycling superstar. Will Damon ride up the Col de la Madone in France? In the rain?
But it's not the only cycle-star biopic likely to be on offer in the next couple of years. Filming has again started on the 'The Flying Scotsman', a £3.3m biopic about Graeme Obree. Trainspotting-star Jonny Lee Miller, Steven Berkoff and Bob Hoskins were due to start filming the pro-bike Scot-flick in the autumn of 2002 but just days before the cameras started rolling the American co-producer keeled over and died, leaving a hole in the movie's budget, killing it.