Clark and Pierce, both New Orleans natives, signed deals with the New York Giants, while Dangerfield signed with the Buffalo Bills.
Clark was a three-year starter in the LSU defensive backfield and he capped his career by starting 36 straight games, including both the Sugar Bowl in 2002 and the Peach Bowl in 2000. Clark recorded 315 tackles and eight interceptions during his four years with the Tigers.
Clark earned Second Team All-Southeastern Conference honors in 2000 after recording 99 tackles and a pair of interceptions.
Pierce was considered to be LSU's most dominating offensive lineman last year, providing the Tigers with a strong surge in its run games. Pierce played in 12 games with 11 starts for the Tigers in 2001.Dangerfield, a Morgan City, La., native, battled injuries most of his LSU career. He did play in 17 games for the Tigers from 1998-2000. He caught seven passes for 102 yards and one touchdown.
There are now four former Tigers who have reached free agent deals with NFL teams. Late Sunday, linebacker Trev Faulk reached a free agent agreement with the Denver Broncos.
Other possible free agency candidates from LSU include defensive back Lionel Thomas, offensive lineman Jason Bagget and tight end Kyle Kipps.