Singleton's signing comes just one day after the Bucs lost starting free safety Dexter Jackson to the Arizona Cardinals via free agency.
Singleton, a six-year veteran, started all 16 games at the strongside linebacker position for the Bucs last season. Singleton was annointed the starter last year after the Bucs decided to move Shelton Quarles over from the strongide linebacker position to the middle linebacker position. Quarles, who also became a free agent this offseason, re-signed with the Bucs last week.
In his first season as a starter, Singleton quietly notched 89 tackles, one interception and one sack during the regular season.
With Singleton gone, the Bucs will likely turn to second-year linebacker Ryan Nece to fill the vacancy at the strongside linebacker position.
Nece joined the Bucs as an undrafted free agent out of UCLA last year. As a rookie, he excelled on special teams until he suffered a torn ACL on his left knee against the Carolina Panthers on October 27. Nece was placed on the injured reserve shortly after his knee injury was diagnosed.
The Bucs will also likely sign a veteran linebacker to compete with Nece and add depth to the linebacker position. The team did not tender a contract to restricted free-agent linebacker Jack Golden.