One player who has played for both teams is defensive end Justin Smith, who joined 95.7 The Game on Friday. The recent Pro Football Hall of Fame nominee likes what he has seen so far from each of his former squads.
"Looking at those two teams right now, they're defensive-led teams," Smith said on the "Joe, Lo and Dibs" show. "The Niners, watching them play, they have a defense, man. They're fun to watch. DeForest (Buckner) in the middle there, I think he's one of the better ones to play in a while. He's wrecking shop.
"For the Bengals, Geno Atkins and the defense they have around him, it's fun to watch. People don't love watching them because they don't put up a ton of points, but I love watching them. They're defensive football teams."
Smith likes what he has seen so far from rookie defensive end Nick Bosa.
"He looked pretty polished from just watching him play," Smith said. "The pass rushes he was beating [the Buccaneers] on, it was all hands. He's not a bull rush guy, so he's got some moves to him, and some shake, and some nasty stuff like that. I think he's going to be fine."
Smith knows the additions of Bosa and Dee Ford will benefit Buckner, who he feels is the defensive lineman opponents really need to focus on stopping.
Smith wasn't the only former 49ers player to find his name on the list of 122 Hall of Fame nominees for the first time. Former linebacker Patrick Willis was also among the distinguished group. Some question if Willis, who played just eight NFL seasons, was in the league long enough to warrant being in the Hall of Fame, much less a first-ballot inductee.
Smith responded: "Is it based on how long you played or how good you were when you played? If it's based on just being the best while you're playing, he's for sure a lock.
"As far as speed, and just how that guy would square people up and take their soul every time he hit them, I've never seen a guy that could square guys up no matter how he was running, no matter what angle he was running at, and get a full helmet-through-their-chest, run-through tackle like he did. It was unbelievable."
You can listen to the entire conversation with Smith below. It begins at about the 35:55 mark.