Midway through the second quarter, the Green Bay Packers outside linebacker, who said this past week that the best way to stop the read-option was to hit the quarterback, tackled Kaepernick out of bounds at the end of a scramble.
Matthews was flagged for a late hit, and it started a scuffle near the Packers bench that resulted in an unsportsmanlike conduct penalty on 49ers tackle Joe Staley.
Even though the penalties offset, it was a costly mistake by Matthews because Kaepernick had run out of bounds and gained only 4 yards on the third-and-6 play. The offsetting penalties call for the down to be replayed, and on the next play Kaepernick threw a 10-yard touchdown pass to Anquan Boldin that gave the 49ers a 14-7 lead.
Lost in the attention paid to the fracas was the fact that on the play before the Matthews penalty, the 49ers were called for an illegal formation on a third-and-1 play in which Frank Gore was stopped for no gain. Packers coach Mike McCarthy accepted the penalty, giving the 49ers another crack at third down. Had the Packers declined it, it would have been fourth-and-1 at the 5.