Bobby Portis is an irritant. Whether it’s running down the court flexing his chest after a key play, a subtle shove into the chest of an opposing player, or some oldfashioned trash talking, Portis has become a master of getting under a player’s skin in his third season in the NBA. And he has not just been irritating his opponents. Ask former teammate Nikola Mirotic, who started the season in concussion protocol after his altercation with Portis in practice on Oct. 17, resulting in Portis punching the forward in the face and breaking two bones. By all accounts, both players were aggressors, with Mirotic having enough of Portis’ trash talk to step toward him before he was hit. Portis is now back to just frustrating opposing players with his antics. And if he can continue to be an offensive force like he was in Thursday night’s 116-115 loss to the Sixers, the Bulls might have a key rotation player for years to come.