I don't understand why people think Jeff Green is playing badly.
He is doing a nice job offensively scoring 9ppg in just 22mpg while shooting 50% from the field and posting a TS% of 57%. He has an excellent post game which gives the Celtics a matchup advantage against most second unit small forwards.
Defensively, he has been really solid at the three and the team as whole has played quality defense when he has been there. He continues to struggle defensively as a four but that is no surprise and even with that he still has value there against certain matchups.
The only thing that has been missing is the rebounding but that is slowly improving.
I don't understand understand why people think he is playing badly. Jeff Green is doing his job.
I think it comes down to expectations. A lot of people thought Jeff Green was a major impact player, and so they were expecting a major impact player off the bench.
However, that's not Jeff Green. He's not a good rebounder, he's not a play-maker, right now he's an average-at-best defender, and realistically, he's a pretty mediocre scorer.
Jeff Green ranks tied for 131st in points per 36 minutes among all players who have averaged 15+ minutes and have played in 20 games this year. In other words, there are 130 players who score more prolifically than Jeff Green. He's not an impact scorer, at least not along the lines of what many thought.
You're exactly right: if anything, Jeff Green has played better here than in OKC.
Per-36 minute stats for OKC: 14.8 points, 5.4 rebounds, 1.8 assists, 43.7% shooting, 30.4% 3PT, .482 eFG%
Per-36 minute stats for BOS: 14.9 points, 4.3 rebounds, 0.8 assists, 49.7% shooting, 30.8% 3PT, .521 eFG%
Green's assists have gone down, and his efficiency has gone up. Everything else has been remarkably consistent (including his rebounding, when you factor in that he's playing more SF now than PF, taking him farther away from the basket.)
If there's any disappointment with the trade, it's because people thought they were getting a potential star, rather than a slightly lesser John Salmons.