Australian Open runner-up Jo-Wilfried Tsonga made an early exit from the Marseille Open when Croatian wild card entrant Mario Ancic beat him 7-5, 7-6 in the first round on Wednesday.
Ancic, back in action after a year out due to mononucleosis, served extremely well on his way to victory over the Frenchman, seeded seventh in the indoor event.
"This is one of the most important wins of my career given the circumstances," said Ancic, a former top 10 player who has dropped out of the leading 100 because of his health problems. "Last year was so frustrating."
Tsonga said his extraordinary start to the year has taken its toll.
"There was a lot of attention and it was difficult for me to prepare for this well," he said. "I feel tired mentally, I need a rest."
Serbia's top-seeded Novak Djokovic, who beat Tsonga in the Australian Open final, easily survived the first round, beating Croatian qualifier Ivan Dodig 6-1, 6-4.
Second seed Richard Gasquet, the French number one, gave the home crowd something to cheer by brushing aside Italian Simone Bolelli 6-3, 6-3.
Russia's Mikhail Youzhny, the third seed, also advanced but was made to work by Croatia's Marin Cilic before pulling off a 6-4, 7-6 win.
Frenchman Gilles Simon, who won the tournament last year, began with a 6-2, 6-4 win over unheralded compatriot David Guez.