For nine seasons with the Pittsburgh Steelers, Harrison was an outside linebacker in a 3-4 defense. Now, after signing a two-year deal with the Bengals, he is taking over Manny Lawson's spot as Cincinnati's strong-side linebacker.
"He can adjust; he was their adjustor in Pittsburgh," Bengals coach Marvin Lewis told the team's official website. "I have no doubt he can do it. He's got that flexibility and he's a smart, hard-working guy. But it all starts with the fact he's physical against the run."
In early downs, though, Harrison might have to drop back into coverage more often than his days in the 3-4 defense. According to Pro Football Focus, Harrison was targeted 16 times in coverage last season and gave up 11 receptions (68.8 percent). He hasn't broken up a pass the past two seasons.
Where Harrison is going to make his impact is on passing downs. The Bengals can line up Harrison and Michael Johnson (11.5 sacks) as ends and team Carlos Dunlap (six sacks) with Geno Atkins (12.5 sacks) inside.
Bengals offensive tackle Andrew Whitworth, who had many battles with Harrison over the years, doesn't think there will be much of a transition for Harrison.
"The days of a two-gap, 3-4 are pretty much gone. Everybody is pretty much playing a hybrid between a 3-4 and a 4-3," Whitworth said. "Even Pittsburgh. Sometimes it looks like they're playing an under 3-4, which kind of looks like an under 4-3. The only difference is that he was standing up instead of with his hand on the ground."