Rohan began his career on the track and was part of the Australian team that took silver medals in the team pursuit at the 2012 Olympic Games.
He joined Garmin-Sharp-Barracuda for the 2013 season and made his Tour de France debut.
In 2014, Rohan finished second overall behind Bradley Wiggins at the Tour of California, after placing second to Wiggins in the time trial. He was also placed second in the Commonwealth Games time trial behind Alex Dowsett.
In August, 2014 Rohan made a rare mid-season transfer to the BMC Racing Team and went on to win the World team time trial championships.
In 2015, Rohan set a new hour record of 52.491 km, beating Matthias Brändle's record by over 600 metres. The record stood until 2 May, 2015 when it was broken by British rider Alex Dowsett.
Rohan Dennis was selected to ride the 2015 Tour de France as part of the BMC Racing Team squad in support of Tejay van Garderen.
He won Stage 1 individual time trial, clocking an average speed of 55.446 km/h (34.5 mph) and became the first Maillot Jaune wearer of the 2015 Tour – with this performance; he established a new record average speed for an individual time trial at the Tour de France.
