World number eight Jo-Wilfried Tsonga was forced to withdraw early in the second set of France's mixed doubles match against South Africa at the Hopman Cup due to injury.
Tsonga appeared to suffer a hamstring strain when stretching for a shot in the latter stages of his 7-6 (7/4) 7-6 (7/3) singles victory over Kevin Anderson that levelled the tie at 1-1.
But when he was in clear discomfort after returning to the court to partner Mathilde Johannson against Chanelle Scheepers and Anderson.
The South Africans took the opening set 6-3 and Tsonga - with one eye on the Australian Open which starts on January 14 - decided to call it quits after three games of the second set, handing South Africa a 2-1 victory.
"I don't know exactly what I have, but I felt something during the singles," he said. "It was a bit short between the singles and the mixed doubles and I didn't have time to know exactly what it was.
"It was a bit sore during the mixed doubles, so for me it was better to quit. I didn't have time for some medical exams, but I cannot take a risk."
Tsonga later withdrew from next week's Sydney International as an added precaution.
Scheepers had earlier beaten Johansson 4-6 6-4 6-4 in the women's singles.