The Sharks said in a statement that an exact timeline for when Hertl could return has yet to be determined. In the interim, the Sharks are expected to monitor Hertl's rehabilitation with the intent to provide an update at a later time.
Hertl, who leads the Sharks with 15 goals and 34 points, said in a statement that he'd been experiencing soreness in his left knee "on and off" throughout the season. He said he spoke with the Sharks' medical staff, who told him that the injury would not get any worse and that he could continue to play through it, which included playing at the NHL All-Star Game in Toronto.
Hertl has been out of the lineup since the Sharks' 5-2 loss on Jan. 27 to the Buffalo Sabres. He missed two games before the All-Star break but did play in the All-Star Game on Feb. 3, when he logged more than 12 minutes.
The Sharks, who were on their bye week, return Thursday to play the Winnipeg Jets.
"After returning from Toronto and having additional conversations with my family and our team medical staff over the last week, I made the decision to have this procedure done now so that I can return to 100 percent as soon as possible," Hertl said. "I look forward to returning to the ice and getting back with my teammates as soon as I can."
Hertl's injury comes as the Sharks (14-32-5) have won four of their last six games, with their most recent contest being an overtime loss to the Anaheim Ducks on Jan. 31.
The Sharks entered Monday two points ahead of the Chicago Blackhawks (14-35-3) for the worst record in the NHL and the strongest odds to win the NHL draft lottery. Boston University freshman center Macklin Celebrini is projected to be the No. 1 pick in the upcoming draft at The Sphere in Las Vegas.