SANTA CLARA — When you think of the Cover-3 defense, you should think of Earl Thomas, Kam Chancellor, and Richard Sherman.
After all, the former Seahawks trio — known as the Legion of Boom — epitomized and popularized the scheme and was the backbone of an all-time great defense that lifted Seattle to its first and only Super Bowl title in 2013.
I apologize for canonizing the 49ers’ rivals, but the context is important: The Cover-3 made life so difficult for 49ers head coach Kyle Shanahan when he was an offensive coordinator for Washington, Cleveland, and Atlanta, he decided to adopt it his team’s defensive scheme when he took over in San Francisco.