The riders have been diverted east after the final major climb of the day, the Col de Puig Major, and will come back onto the original route 10 kilometres before the finish.
It is a sinking road near Lluc that has caused the riders to have to divert from the route originally laid out by race organisers. Photos show one side of the road has completely fallen away.
One lap of the opening loop around Andratx has been removed to accommodate the extension from Lluc towards Pollenca, where the riders turn southwest to head back towards the final part of the original route. The change has increased the total distance from 168.5km to 173.3km.
The riders will ride from Andratx to Lloseta with three categorised climbs. The Col de Puig Major tops out just under 70km from the finish, with a descent followed by a flatter run to the finish.
Jesus Herrada (Cofidis, Solutions Credits) took victory on the opening day on Thursday on top of the Puig de Sant Salvador ahead of Guillaume Martin (Wanty - Gobert Cycling Team), Bauke Mollema (Trek - Segafredo). World champion Alejandro Valverde (Movistar Team) finished fourth and is racing again on Friday.
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