Whereas Smith's GC team-mate Guillaume Martin is a distant hope for the top place, the other three will be locked in an intriguing battle to support their team leaders.
Bevin's Australian BMC leader Richie Porte has high hopes this will finally be his year, after crashing out in 2017. Porte last month won the Tour of Switzerland. Jack Bauer will be working to support in-form Briton Adam Yates at Mitchelton-Scott and Scully will be in the service of the 2017 runner-up Rigoberto Uran of EF Education First-Drapac.
Smith, riding in his second consecutive Tour, is the one Kiwi most likely therefore to be let off the leash to try his luck at a stage win in a breakaway group. Bevin is an outside chance to briefly put on the leaders yellow jersey, depending on the outcome of the stage three team time trial.