The NBA and National Basketball Players Association have made significant progress toward a new Collective Bargaining Agreement, and there is strong optimism among officials on both sides that a deal could be finalized in the next several weeks, league sources told The Vertical.

The NBA and NBPA each have until Dec. 15 to exercise an opt-out clause of the current 10-year deal that was reached in 2011, but sources on both sides believe that a new deal will be in place prior to that date.

An agreement will eliminate the possibility of a work stoppage in 2017.

During several months of discussions, NBA commissioner Adam Silver and NBPA executive director Michele Roberts, as well as their respective committees and staffs, have agreed upon many of the significant collective bargaining issues, league sources said. Much of the remaining talks are centered upon smaller elements of the CBA, league sources said.

From the outset of the talks, there has been a spirit of cooperation between Silver and Roberts, largely reflective of strong economic times in the NBA.

Among expected changes in the new CBA, league sources told The Vertical: A significantly higher rookie contract scale and two-way contracts between the NBA and NBA Development League that will add playing jobs for the union.

The NBA and NBPA were unable to reach a labor deal in 2011 until December, costing teams 16 regular-season games.

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