Nick Kygrios has withdrawn from his BNP Paribas Open quarterfinal against Roger Federer due to illness.
Kyrgios upset No. 2 seed Novak Djokovic in the fourth round and was due to play Federer for just a second time, having won their only previous meeting in Madrid in 2015.
Federer will play either Kei Nishikori or Jack Sock in the semifinals.
"I am unable to play today due to sickness," Kyrgios said in a message posted on his Twitter account. "I don't take these decisions lightly... but I’m in no fit state to take to the court. I’m sorry to the fans."
Federer shared Kyrgios’ post, writing to Nick, "Hope you feel better Nick."
Friday's revised order of play opens with an exhibition match between Canada's Vasek Pospisil and BNP Paribas Open tournament director Tommy Haas at 12:45pm PDT. The men's quarterfinal between Jack Sock and Nick Kyrgios starts at 2pm PDT, followed by a men's doubles semifinal between fourth seeds Murray/Soares and No. 8 seeds Kubot/Melo.
The evening session (not before 7pm start) will feature the women's semifinals: No. 28 Kristina Mladenovic vs. No. 14 Elena Vesnina followed by No. 3 Karolina Pliskova vs. No. 8 Svetlana Kuznetsova.
The updated order of play can be found here.