Williams, for his part, could wind up playing an important role with the departure of Gardener, who was released after the trade with the Panthers was consummated.
"We are pleased to trade for Jay," Coach Dave Wannstedt said in a prepared statement. "He is a solid all-around defensive end that can play the run and be an effective inside nickel pass rusher."
Williams played for Carolina for two years after spending his first six NFL seasons with the Rams. Ironically, Williams joined the Rams in 1994 after spending part of training camp with the Dolphins.
Williams started three games during his time with the Rams, but earned a Super Bowl ring during the 1999 season. He started 27 games in his two seasons with the Panthers and had a career-best six sacks in the 2001 season. Last year, Williams finished with 27 tackles, one sack and one interception.