Wimbledon champion Andy Murray lost his comeback match from a three-month injury layoff in the opening round of the Mubadala Championship on Thursday.
Murray lost 7-5, 6-3 to Jo-Wilfried Tsonga in 72 minutes.
Tsonga will meet Novak Djokovic in the semifinals of the exhibition event on Friday, while Rafael Nadal will take on Spanish compatriot David Ferrer in the other semi.
Ferrer, who last week dumped his longtime coach Javier Piles, beat Stanislas Wawrinka of Switzerland 7-5, 6-1.
Murray, who hadn't played since Davis Cup in mid-September because of a back complaint, kept pace with Tsonga until 5-5. Even to that point, Murray's rustiness was obvious with accumulating unforced errors. After Tsonga broke Murray for the first time, he stayed in charge.
"I was feeling fine with my body and the knee, and this win over someone like Murray is going to give me great confidence as I start the new season," Tsonga said.