No. 3: Defensive Tackle Arik Armstead
The 49ers have been vulnerable against the run this season, allowing an average of 4.7 yards per rush attempt in 2019. And life won’t get any easier after the team lost linebacker Kwon Alexander to a season-ending pectoral tear in Arizona.
Alexander’s absence is something to watch, yes. But a quality run defense ultimately starts up front with the defensive line.
A chief player to watch in this regard is defensive tackle Arik Armstead, who is again quietly emerging as one of San Francisco’s best defenders, both against the run and the pass.
Focusing on the run game, considering Seattle’s tendency to run the ball, Armstead will look to clog a lot of the interior run attempts by Seahawks running back Chris Carson, who is averaging 4.4 yards per attempt this season.
According to Pro Football Focus, Armstead is the No. 1 ranked run defender among qualifying edge rushers, posting an elite-level 91.0 grade in this category.
Look for Armstead to be a major reason behind any San Francisco success stopping the run.