Upcoming key NFL dates for the Detroit Lions:
— Feb. 17-23: NFL Scouting Combine, Lucas Oil Stadium, Indianapolis.
— March 2: Prior to 4 p.m., deadline for clubs to designate franchise or transition players.
— March 7-10: Clubs are permitted to contact, and enter into contract negotiations with the certified agents of players who will become unrestricted free agents upon the expiration of their 2014 contracts at 4 p.m., on March 10. However, a contract cannot be executed with a new club until 4 p.m., on March 10.
— March 10: Top-51 begins. All clubs must be under the 2015 salary cap prior to 4 p.m. All 2014 player contracts expire at 4 p.m. The 2015 league year and free agency period begin at 4 p.m.
— April 20: Clubs with returning head coaches, like the Lions, may begin offseason workout programs.
— April 24: Deadline for restricted free agents to sign offer sheets.
— April 30-May 2: NFL Draft, Chicago.