Free-agent center DeMarcus Cousins has reached agreement on a one-year, $5.3 million deal with the NBA champion Golden State Warriors, league sources told Yahoo Sports.
According to Wiki, a free agent means:
In professional sports, a free agent is a player who is eligible to sign with any club or franchise; i.e., not under contract to any specific team.
But what does "Free-agent center" truly mean in this sentence? Is it a center where all the free agent are gathered, or DeMarcus Cousins himself is the Free-agent center implying he is a 'center' person amongst all the others? I speculate the latter according to the context, but I am not quite sure.
A side question: why is there not any article preceding free-agent center, like "A free-agent center" or "The free-agent center"?
The full source.