I don't think painting Doc as the bad guy here is good. Before Rondo got injured, Green was the 4th or 5th option on our team. Afterwards, he became the 2nd or 3rd option (also given PP not playing his best). You make more plays for the 2nd or 3rd option on a team than you do for the 4th or 5th option.
Also, Green had been getting a whole lot better before Rondo got injured. His numbers were going up (which is natural; he's getting more adjusted to the game after his chest got broken open).
So, I don't think it's a coincidence; it's not Rondo or Doc's fault that he wasn't playing as well earlier in the season; and I think if he keeps playing this well (averaging 17 ppg, outbursts like the Suns game every few weeks), he will not only be up for a starting spot on the team, he might get 6th man of the year.