World number nine Jo-Wilfried Tsonga has suffered a shock defeat to wildcard Thiago Monteiro in the first round of the Rio Open.

The Frenchman, who was seeded third in the tournament, was on the losing end of a 6-3 3-6 6-4 scoreline in a rain-affected match.

Monteiro, who is ranked 338th in the world, earned a double break to take the first set, but he was dealt an early blow in the second when he lost his opening service game.

Tsonga later broke again to draw level on sets, but Monteiro battled through to take the third and earn himself a spot in the second round.