The Panthers were left with a hole on the defensive line after starter Maake Kemoeatu, Carolina's top run-stuffer, ruptured his Achilles' tendon less than 30 minutes into the first practice of training camp.
While the Panthers still might look to get more help at the position, the 6-foot-4, 325-pound Leonard could contend for the starting job. Leonard played all 16 games for the Browns last season, including four starts, and had 31 tackles.
"Getting him in here right now, we'll get a little over 10 days to work with him and at least put him in the rotation," Panthers general manager Marty Hurney said. "We'll see how it all works out. We think he's got ability and we think he's a good player. He's 25 years old, he's young and he's continuing to improve. We certainly feel like he can be in the mix."
In turn, the Browns get a late pick for a player who was no lock to make the regular-season roster. Leonard recently got into an argument with defensive line coach Bryan Cox during practice and was forced to run laps. He also might have been an odd fit in Cleveland's 3-4 defense.
In Carolina, Leonard likely will quickly move to the front of a thin group. Nick Hayden, who has played in two NFL games, and undrafted rookie Marlon Favorite have been alternating as starters. The Panthers struggled defending the run in two of three preseason games.
The Panthers made roster room for Leonard by waiving undrafted rookie defensive tackle Lonnie Harvey. Carolina then placed reserve safety Nate Salley on season-ending injured reserve to get to the 75-player limit. Salley had been unable to practice for weeks because of a knee injury.
Leonard was signed by the San Diego Chargers in 2007 after going undrafted out of Fresno State. He was later waived by the Chargers and St. Louis Rams before signing with the Browns during the middle of the 2007 season.
Leonard could see some time in Thursday's preseason finale against the Pittsburgh Steelers. But Hurney wouldn't rule out making more moves to help with depth at defensive tackle.
"We're going to continue looking everywhere," Hurney said. "We'll remain flexible like we always try to do."
Copyright 2009 by The Associated Press