Serbia's Viktor Troicki upset Jo-Wilfried Tsonga in the semi-finals of the Thailand Open in Bangkok.

Troicki, seeded fourth in the tournament, looked to be on his way out when Tsonga triumphed 6-1 in the first, but battled back to take the match 1-6 6-3 6-2 in one hour and 38 minutes.

The world number 32 will take on another Frenchman, Gilles Simon, in the final.

Second seed Simon got past Austria's Jurgen Melzer in his semi-final 6-4 7-6 (7-3).