The Suns announced Thursday that Lawal was injured during practice Thursday morning at US Airways Center. How Lawal hurt his knee wasn't immediately disclosed.
The team says Lawal underwent an MRI exam that revealed a torn anterior cruciate ligament and a partially torn medial collateral ligament. Suns officials say Lawal will undergo surgery once swelling in his right knee subsides, which may take up to two weeks.
Lawal was drafted by Phoenix in the second round at No. 46 overall. The former Georgia Tech standout played 10 games for Iowa in the NBA Development League and made his debut with the Suns on Dec. 31.