Having suffered early on, Kwiatkowski fought his way back to the ever-fluctuating group that contained Sky's Chris Froome, finally making contact on the Col de Val Louron-Azet, the day's penultimate climb.
"I just want to say thank you to my teammates because they pushed me to the limit," the Polish Road Champion tells Cyclingnews in this video. "I was in trouble from the beginning of the stage."
Kwiatkowski has posted results across all disciplines so far this year, with podiums at the Tour de San Luis, second overall at Volta ao Algarve, top-five placings at Amstel Gold Race and Flèche Wallonne before taking out his national championship.
Kwiatkowski held the lead in the young rider's classification for six stages of the first nine and the all-rounder has not given up hope of regaining the white jersey despite the gauntlet currently being thrown down by Nairo Quintana (Movistar).
Watch more of Kwiatkowski's comments after what he called the "hardest stage in this Tour," in the video below.