
The Frenchman triumphed 6-4 0-6 7-5 to reach his first Masters final since he triumphed in Toronto last year.
The 30-year-old fired down 11 aces to record his first win over Nadal since the 2011 ATP World Tour finals.
Nadal, a winner of 14 Grand Slam singles titles, struggled to cope with Tsonga in the opening set as the Frenchman pressured the Spaniard’s serve with some heavy hitting.
The victory gives a major boost to his flagging hopes of qualifying again for the end of season Championships in London.
However, Novak Djokovic produced an imperious performance to cruise to a 6-1 6-3 victory over Andy Murray.
British number one, Murray, was brushed aside in the first set by the Serbian as he won just one service game.
The 28-year-old Scot showed some fight in the second set, but never really threatened as Djokovic served out.