A trade for the NFL's active sack leader spiced up a rainy Monday night at Bank of America Stadium.

News of the Carolina Panthers' deal for defensive end Jared Allen dropped shortly before the team's weekly "PantherTalk" radio show. In front of the crowd gathered for the live event, coach Ron Rivera said the Panthers started trade talks Monday morning, a day after Charles Johnson re-aggravated a hamstring injury.

"We didn't want to wait when we found out there was an opportunity," Rivera said.

"[Allen's] a pass rushing specialist. He plays the run very well; he's a physical guy. He's got good size, good hand strength, he rushes with violence, he doesn't just sit there and work one way or the other. He's got counter moves. We watched a lot of tape on him today to make sure this could potentially be a fit for us."

Unlike receiver Kevin Norwood, who's played 13 offensive snaps since the Panthers acquired him four weeks ago, Rivera said Allen should be able to acclimate quickly. Not only is he a 12-year veteran, but "for the most part, defensive linemen really just go in one direction, and that's upfield."

Of anyone around the Panthers' organization, few are as familiar with Allen as former offensive tackle Jordan Gross. The two went head-to-head four times, first when Allen was a rookie in Kansas City, and then when he was starring in Minnesota. In those meetings, Allen totaled 14 tackles and two sacks.

"He's very instinctual, so I think he doesn't necessarily have a move he's going to do before the ball is snapped. He's very tough to read, he doesn't have a lot of tells," Gross said. "I think he would age well because he never was incredibly explosive off the ball, never was incredibly strong, but just a good, technical pass rusher.

"He just wants to get to the quarterback; he's not worried about beauty points."