Milwaukee Bucks forward Khris Middleton will undergo surgery to repair a torn hamstring and his status for this season is unclear, league sources told The Vertical.

Middleton, 25, suffered the injury in workouts Tuesday and subsequent testing revealed the tear, sources said.

He could miss a significant portion of the season and a final timetable will be set after surgery, sources said.

Middleton averaged 18.2 points, 4.2 assists and 3.8 rebounds in 79 games last season. His injury is a significant loss to a Bucks roster that hoped for continued growth this season around Middleton, Giannis Antetokounmpo, who signed a $100 million extension Monday, and Jabari Parker.

The Bucks also signed wings Orlando Johnson and J.J. O’Brien to compete in training camp.

Middleton is entering his fifth NBA season after being selected with the No. 39 pick in the 2012 NBA draft. He signed a five-year, $70 million contract in 2015.

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