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If the two sides cannot reach an agreement before Oct 31, Gibson will become a restricted free agent at the end of this season.
Jay Patt of Blog a Bull estimates that $8 million per year would be a fair value. Anything less, he says, would be a steal.
Gibson has been with the Bulls since 2009, when the team selected him in the first round of the NBA draft. In three seasons, the former USC Trojan has averaged 7.9 points and 6.2 rebounds per game.