North Carolina basketball guard Cameron Johnson is undergoing surgery today for a torn meniscus in his left knee, an injury he suffered in practice Monday. UNC expects to release more information after the surgery at UNC Hospitals is complete. Johnson joined the UNC program before this season after playing for three seasons and graduating with honors from Pittsburgh. “I’m extremely disappointed for Cameron,” Coach Roy Williams said in a statement. “The young man has been working hard to blend in with our team after being such a productive college player the last two-plus seasons.”