South Africa international Pat Lambie is expected to miss six to eight weeks of action with a fractured vertebrae in his lower back.
The fly-half was injured in a tackle during the early stages of Sharks' 37-14 victory over Waratahs on Saturday, with teenage replacement Curwin Bosch stepping up in Lambie's absence with 27 points.
Lambie, who has 56 caps for his country, is now set for a period on the sidelines to recuperate from the setback.
"It is difficult to say exactly how long the approximate length of recovery will be in Pat's case, as he undergoes further scans, but his return is estimated at six to eight weeks," Sharks team doctor Alan Kourie said via the club's official website.
Lambie will hope to have recovered in time for the Springboks' three-Test series against France, which starts on June 10.