Marcus Smart had to learn the hard way that punching any sort of glass-based object may be hazardous to your health.

The Boston Celtics guard, who has not played since lacerating his right hand striking a picture frame last month, said on Wednesday that he needed a shard of glass removed from the hand, per ESPN’s Chris Forsberg. Smart also revealed that he likely would have needed season-ending surgery if the shard struck a tendon, which it did not.