In a decisive 23-13 victory over the Tennessee Titans, former USC Trojans quarterback Sam Darnold scored three touchdowns, and the Minnesota Vikings improve to 8-2. Darnold has 20 or more touchdowns for just the second time in his career.

Controversy reigned in the second quarter, when an unnecessary roughness penalty on a hit by Mike Brown on Addison wiped away a Titans goal-line stand. One play later, Sam Darnold snuck into the end zone on a 1-yard run.

Why was Tennessee Titans safety Mike Brown penalized for unnecessary roughness vs the Vikings Sunday? Here's what an NFL referee said.