Roger Federer was knocked out of the Monte Carlo Masters when he slumped to a 3-6, 6-2, 7-5 defeat by local favorite Jo-Wilfried Tsonga in the quarterfinals on Friday.
The Swiss third seed was back in action this week after a 10-week layoff during which he underwent knee surgery.
Earlier, there were glimpses of the formidable Rafa Nadal as the eight-time champion swept aside French Open winner Stan Wawrinka 6-1, 6-4.
The Spaniard will take on Andy Murray for a place in the final. World No. 2 Murray raced into last four with a 6-2, 6-0 demolition of Canadian Milos Raonic.