"That young guy has so much potential, and he's gifted," Willis told Matt Maiocco on the latest 49ers Insider Podcast. "You can obviously tell the way he plays, the way he attacks the ball. I hope he learns to take care of himself in the aspect of his body."
Worried about his future health, Willis decided to retire from the NFL in 2015. The 49ers selected him with the 11th-overall pick in 2007, and he was named the NFL Defensive Rookie of the Year after finishing his rookie campaign with an NFL-leading 174 total tackles.
Willis went on to be selected to seven Pro Bowls and was a five-time first-team All-Pro over his eight-year NFL career. He registered 50 tackles, 20.5 quarterback sacks, eight interceptions, 16 forced fumbles, and two touchdowns during his time in the league.
As for Foster, Willis is hoping the young linebacker can learn to protect himself better. The budding 49ers star missed six games during his rookie season due to various injuries. He sustained a concussion on Saturday against the Indianapolis Colts.
"He has to start learning when to give those certain kind of looks and when to throw his body in there a certain kind of way and different things like that because he doesn't want to keep getting banged up too much like that," Willis continued. "He'll wisen up to some of that. Other than that, he is going to be who he is. He's from the SEC, so I know he's going to lead those guys there."
You can listen to the entire interview with Willis below.
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