In professional sports, a free agent is a player or manager who is eligible to sign with other clubs or franchises; i.e., not under contract to any specific team.
Free agency was severely restricted in many sports leagues, instead clubs had a reserve clause which allowed them to retain players indefinitely.
A notable case of this being Sol Campbell who in September 2009 was released from Notts County, just after a month from signing on a free transfer.
He signed for his former club Arsenal in January 2010 during the winter transfer window, after spending a few months training with the team to maintain his fitness.
[2] Unrestricted free agents (UFAs) are players with expired contracts that have completed four or more accrued seasons of service.
[3] Exclusive-rights free agents (ERFAs) are players with two or fewer seasons of service time and whose contracts have expired.
In addition, any player at least 22 years of age who has not been selected in the NHL entry draft can sign with any team as a free agent.
[10] In Major League Rugby, a player can be signed by any team as a free agent at 18 years old as long as they don't enroll in college.
For example, under the most recent NHL Collective Bargaining Agreement, restricted free agents who do not sign contracts by December 1 of a given year will be ineligible to play in the National Hockey League for the balance of that season.
They have either been released from their club, had the term of their contract expire without a renewal, or were not chosen in a league's draft of amateur players.
These people, generally speaking, are free to entertain offers from all other teams in the player's most recent league and elsewhere and to decide with whom to sign a contract.
In the NFL, numerous of notable highly touted free agents have signed with other teams, with the tenures being busts.
The highly coveted defensive tackle signed with the Redskins for a seven-year, $100 million deal which ultimately busted with his laziness and ineffectiveness on the team.