"Unfortunately Rafal Majka will not start stage 17 of the Tour de France today," the UAE Emirates team said in a statement before the 130-km mountain trek to Peyragudes.
Majka has been Pogacar's key lieutenant in the mountains.
It leaves the young Slovenian, who trails overall leader Jonas Vingegaard by 2:22, with only three team mates for the final days of the Tour. And one of whom - Marc Hirschi - has been struggling throughout and has not been able to provide Pogacar with any help.
"Majka sustained a strain injury to his thigh after some mechanical trouble on stage 16 when his chain broke," team doctor Adrian Rotunno said.
"This resulted in a high-grade partial thickness tear of his right quadriceps muscle, and unfortunately due to the muscle damage he is unable to ride."
