Now it will be costing him a chunk of his paycheck as well.
The NFL has fined the linebacker $15,000 for hitting Kaepernick out of bounds during last Sunday's game in San Francisco, according to Adam Schefter.
The hit occurred as the quarterback was attempting to run out of bounds on a 3rd-and-9 play during the second quarter. Matthews launched himself at Kaepernick (click for gif) despite the fact that he was well out of bounds, sparking a shoving match between the two teams and bringing down a shower of yellow laundry.
During the scrum, 49ers lineman Joe Staley was assessed an unsportsmanlike conduct to match Matthews's late hit. The two flags should have resulted in offsetting penalties and a fourth down. Instead, referees incorrectly allowed San Francisco to replay third down, and the 49ers took advantage by gaining the first and later scoring a touchdown on the drive. The Packers would eventually lose by six points.
On Friday, Matthews responded to criticism from 49ers head coach Jim Harbaugh, stating via Pete Dougherty that "I'm an awesome player, not a dirty player."