Clemons began his pro career after attending an ELITE Regional Combine in 1994 when the Winnipeg Blue Bombers signed him. He played three seasons in the CFL before making the jump to the NFL.
The Saints signed Clemons to an offer sheet in February 2000, hoping to steal him from the St. Louis Rams. When the Rams failed to match the offer the Saints had there man and a player the new regime of GM Randy Mueller and Head Coach Jim Haslett had targeted. "Charlie is another guy we targeted to come in here and start and we are pleased he is a Saint," said Mueller. "He offers us a versatile player that can rush the passer and is a good run stopper in the middle."
Clemons caught the eyes of Saints management while with the Rams, whom he won a Super Bowl with in 1999. Clemons recorded 44 tackles (28 solo), three sacks (20 yds.), an interception, five passes defensed, a fumble recovery and 16 quarterback pressures during that Super Bowl season. He had earned his way up the Rams depth chart after signing with the club in 1997 from the CFL.
In 2001, Charlie established himself as an elite NFL linebacker, finishing 4th in the NFL in sacks with 13.5. He was behind only Michael Strahan (22.5), Peter Boulware (15) and Leonard Little (14.5). It was a tremendous accomplishment and erased any doubts about his health after he missed the entire 2000 season with an Achilles tendon injury.
He played in all 16 games for the Saints in 2002, starting 14 at MLB, recorded 112 tackles, three fumble recoveries, two forced fumbles, one-half sack and five passes defended.
Charlie finished his 10 year pro career with the Houston Texas in 2003. He signed with the Texans as an unrestricted free agent on April 2, 2003 after spending the prior three seasons with the New Orleans Saints.