McRoberts underwent an MRI on Monday, which revealed the injury. Heat coach Erik Spoelstra confirmed McRoberts will need surgery.
"It’s tough," Spoelstra told reporters. "You feel for him more than anything else because you wanted him to come in here and contribute.
"You started to see flashes of it. It’s ironic that his best game really was the Phoenix game and that play happened in the last minute."
McRoberts last played Dec. 9 vs. the Phoenix Suns, scoring 10 points with seven assists and four rebounds in a 103-97 Heat win. According to the South Florida Sun Sentinel, he was injured in the "latter stages" of the game and was initially diagnosed with a bruised knee.
McRoberts, 27, signed a four-year, $23 million contract with the Heat in July. He spent the past two seasons with the Charlotte Bobcats developing into a power forward with three-point shooting range and strong passing skills, averaging 8.5 points, 4.8 rebounds and 4.3 assists per game last season.
- Mike Fiammetta