Top seed Roger Federer lost in the second round of the Madrid Open to 20-year-old Australian Nick Kyrgios.
The Swiss world number two, a three-time winner of the tournament, was beaten 7-6 (7-2) 6-7 (7-5) 6-7 (14-12).
Federer, 33, took the first set on a tie-break but Kyrgios fought back and will now play American John Isner.
Third seed Rafael Nadal, looking for a fifth Madrid title in his home country, beat American Steve Johnson 6-4 6-3 and will play Italy's Simone Bolelli.
Britain's Andy Murray plays Philipp Kohlschreiber in his second round match later on Wednesday, just two days after beating the German in the Munich Open final.