The eighteenth stage of the Vuelta a España is highly anticipated, with a critical time trial expected to shake up the general classification. Race leader Enric Mas of Movistar is attempting to maintain his composure, but his time trialling ability is historically a weakness. He built his lead in the mountains and now must defend it against rivals. Primož Roglič of Bora, currently third overall, poses the biggest threat and is expected to make significant gains. The key question surrounds how much time Roglič can close on Mas. Fans can follow live coverage of this pivotal stage beginning at 14:00.