Holeček has received the 2018 Piolet d'Or[1] award for his successful full ascent on the southwest face of Gasherbrum I with Zdeněk Hák, which he achieved in Alpine style.

[2] „My body has been systematically tortured for years in achieving one important skill for staying in the mountains, the art of hardship.

"[3] It took Holeček five attempts to finally complete his new route up the Southwest Face of Gasherbrum I, situated in the Baltoro region of Pakistan's Karakorum.

Together with his climbing partner, Zdeněk Hrubý, he solved the first crux of the mixed terrain, an unclear passage from the couloir to the col, through the rock bottleneck at 7,400 meters, after their second bivy.

[14][15] In 2013, the attempt ended tragically for Zdeněk Hrubý who slipped and tumbled to his death, taking all their climbing gear with him.