Klay Thompson is reportedly set to undergo an MRI after the Golden State Warriors confirmed the star suffered a leg injury during practice.

Thompson has been working his way back to full fitness after sitting out the entire season due to a torn anterior cruciate ligament (ACL) sustained in Game 6 of the 2019 NBA Finals.

Now, the Warriors – who are looking to bounce back after their forgettable 15-50 season – are sweating on Thompson's fitness following his latest setback.

Thompson is believed to have felt pain in his calf during a workout in Los Angeles on Wednesday, with the three-time NBA champion reportedly scheduled to have an MRI on Thursday.

The five-time All-Star has been rehabilitating for more than a year – Thompson took part in his first full practice with the Warriors in September, 470 days following the ACL injury.

Golden State used the second pick to draft center James Wiseman on Wednesday and he was rocked by the news midweek.

"As soon as I seen [the news], it was kind of down for me, like emotionally," Wiseman said. "But the team, we got his back no matter what and he's going to be in great recovery.

"And from my perspective, I just can't wait to go in there and give my great contribution towards the team and just go in there and learn as much as possible.

"Just grow and adapt within that environment and just play my position. But all prayers be to Klay, my team-mate, and he's going to be just fine."

Since being drafted by the Warriors as the 11th pick in 2011, Thompson has a career average of 19.5 points, 3.5 rebounds and 2.3 assists per game.

In 2018-19, Thompson averaged 21.5 points, 3.8 rebounds and 2.4 assists per game as the Warriors eventually fell to the Toronto Raptors in the Finals.