Nathan Berry will miss the ride on Unencumbered in Saturday's Todman Stakes after being diagnosed with viral encephalitis in Singapore. Berry collapsed at trackwork at Kranji racecourse on Tuesday morning and was taken to hospital for scans. "Nathan seems to have viral encephalitis. He has been placed on medication and will remain in hospital for the next 48 hours," said Berry's manager Ryan Roberts. Berry's twin Tommy, who rode Unencumbered in a recent barrier trial, will ride the Bjorn Baker trained colt on Saturday. Viral encephalitis is an inflammation of the brain caused by a virus.