The Pistons won’t have their big man to start the season. During Tuesday night’s preseason game Marvin Bagley appeared to slip while playing defense. His right knee slightly hyperextended and collapsed inward. The immediate concern based on this mechanism of injury is damage to the MCL, which is the ligament that runs along the inside of the knee. An ACL tear is also possible when the knee hyperextends, but this one didn’t look too severe.
An MRI on Wednesday confirmed my initial suspicion that Bagley suffered MCL damage. It also showed a bone bruise. He is expected to be sidelined for 3-4 weeks, so he will miss the start of the season. The MCL (medial collateral ligament) typically heals well on its own, but it can take a significant amount of time (over a month). A bone bruise is the same – while it isn’t structural, it can be very painful until it fully heals.
The Inside Injuries algorithm has this as a grade 2 (moderate) knee sprain. The Optimal Recovery Time is five weeks, so if he returns when expected he will still come with a High Injury Risk and a lower projected performance.
Bagley averaged 11.3 points and 7.0 rebounds after being traded to the Pistons at the trade deadline last season. He was previously with the Kings since being drafted in 2018.