Novak Djokovic has been knocked out of the Monte Carlo Masters by world number 55 Jiri Vesely.
The world number one was beaten 6-4 2-6 6-4 by the Czech, his first exit as early as the second round since the Madrid Masters in 2013.
Vesely, 22, had never before beaten a player ranked in the world's top 10.
Eleven-time Grand Slam winner Djokovic had won his past 22 matches in Masters competitions and nine of his past 10 tournaments.
The Serb had won the Monte Carlo title in two of the past three years, but struggled as Vesely attacked his second serve and used the drop-shot to great effect.
In round three, the Czech will play 13th seed Gael Monfils, who beat Paolo Lorenzi 6-2 6-4.