As most media outlets reported quickly, the Panthers traded for mammoth DT Louis Leonard. The 6'4, 325 lb run stopper is going into his third year in the league, having been a star at Fresno State with 28 starts, registering 68 tackles and 6.5 sacks. He was a teammate of current Panthers cornerback Richard Marshall at Fresno State.
The 3-4 veteran has 4 games started in his career, all with Cleveland. He played in 20 games over 2007-08 under Romeo Crennel in the 3-4, starting four. Primarily playing 3-4 defensive end, Leonard also played time at nose tackle. Before going to Cleveland, he was with St. Louis under DL coach Brian Baker for six weeks, and before that was in camp with the San Diego Chargers.
Leonard is a wide-body, run-stopping depth player at DT, and a good fit for the nose tackle position vacated by Maake Kemoeatu. He's a part time player at DT, and probably a rotational player. He's never played in a one-gap scheme before, so he probably doesn't fit as a penetrator; he doesn't have a great first step, he doesn't slip blockers, and he isn't the athletic player to run to the ball. But he's the type player to hit the center in the mouth, require a second blocker, and hopefully help the defense stop the run.
On the heels of the Leonard trade, NFL.com states that the Panthers are likely to sign DT Alfonso Boone. The former Chief and Bear was cut Tuesday; the 9th year DT opened Chiefs camp as a starter as the team moved to the 3-4 but Boone didn't fit. He has experience in the one-gap Tampa 2, having started 18 games with the Bears from 2001-06; he moved to the Chiefs in 2007, starting 15 games; he was moved to DE in 2008, starting four more contests.
Boone's experience makes a lot of sense; he doesn't fit as a NT specifically well, but would be a good run stopper.