Memphis Grizzlies forward Zach Randolph sits on the bench in the second half of Game 6 of an opening-round NBA basketball playoff series against the Oklahoma City Thunder, Thursday, May 1, 2014, in Memphis, Tenn. Oklahoma City won 104-84 to even the series 3-3. (AP Photo/Mark Humphrey)

The Memphis Grizzlies and forward Zach Randolph have reached an impasse in contract extension talks and the two-time All-Star forward is thinking seriously about triggering his early termination option and becoming a free agent, league sources told Yahoo Sports.

Randolph's agent, Raymond Brothers, has been in steady talks with general manager Chris Wallace and Grizzlies ownership for several weeks, but the sides have dug in recently and have been unable to find common ground – specifically on the length and money of the deal, sources said.

Randolph, 32, has until June 30 to trigger a $16.5 million player option on the final season of his contract. If he opts out, he can become an unrestricted free agent July 1.

An extremely popular figure in the Memphis community, Randolph has expressed a strong desire to finish his career in the city where his NBA career has truly blossomed. The Grizzlies have been trying to secure him with an extension, but the sides haven't been able to get together on the length and money of the deal.

For Memphis, Randolph was essential to holding together a core that won 50 games and advanced to a Game 7 against Oklahoma City in the first round of the Western Conference playoffs.

Randolph has twice been an All-Star for the Grizzlies. He averaged 17.4 points and 10.1 rebounds this past season.