By "it" I mean being more aggressive and fitting better into the celts' system. As far as aggressive foes, I guess maybe never. As far as understanding the celts' system, probably after next year's training camp. As I said, he likely will be trade bait next year anyway.
I wonder how useful a trade asset Jeff Green will be if you have to give him a large contract. I am expecting a $40 million five year type deal (similar to Marvin Williams). I don't know how useful an asset he'd be at that point.
Plus, even if Green did sign the qualifying offer, that would make him an unrestricted free agent the following summer and any team that acquires him would risk losing him and be hesitant to give up a major trade asset as a result.
I am not 100% sure but I think a player loses his bird rights if he is traded at any time during that season after signing a qualifying offer ... plus you'd need Jeff Green's consent to make the trade due to the qualifying offer which further complicates things (which considering he'd be losing his bird rights may be tough to do).
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Maybe a mid first round pick + an expiring contract.
That would be my expectation of Green's trade value in either of those scenarios. Unless some GM is head over heels in love with him, I'm not sure you get more than that.
With the C's potential cap space being more valuable (why expiring contract + pick being preferable) than most veterans on long term contracts being offered (say a Jose Calderon level player).