The San Francisco 49ers focused on improving their defensive depth in free agency.
Kyle Shanahan's team did not need to make any massive splashes, but it had to add more second-tier impact players to replace the ones that departed in the offseason.
Some of those depth players will play more important roles throughout the season, starting with linebacker De'Vondre Campbell.
Campbell has the potential to get off to one of the better starts on the defense with Dre Greenlaw working back to 100 percent after his torn Achilles.
The defensive line also carries a lot of potential for improvement around Nick Bosa.