Green not living up to Celtics’ hopes … yet

Unfortunately for Boston, Jeff Green is playing much like he did in OKC. (Brian Babineau/NBAE via Getty Images)

As I wrote when it happened, Boston’s Jeff Green/Kendrick Perkins swap amounted in part to a recognition among higher-ups that the team’s offense and bench may not have been good enough to win a championship. Green, with his range and versatility, was brought over to help loosen up the Celtics’ spacing, provide the option to go small and give Paul Pierce a true backup in the wake of the Marquis Daniels injury. The risk was that Green would muck things up on defense; the Thunder had played siginficantly worse on that end with Green on the floor in every season since he entered the league.

After a five-week honeymoon period, some Boston fans and Celtics beat writers are starting to raise questions about Green — and Green himself is openly discussing the work he must do to improve his defense. The writer types (and Doc Rivers, too) are talking about Green’s need to assert himself on offense, his dismal defensive rebounding rate and whether he’s being too “nice” on the court.

Integrating a player like Green is a big challenge. He is learning a radically different defensive system than the one he played in Oklahoma City, and he can swing between both forward positions. That kind of versatility is nice, but it means Rivers has to experiment with Green in various combinations to find out what works and what doesn’t. Rushing that process over the final two dozen games of the regular season, so that Boston and Green are playoff-ready, is not an easy thing.

And yet, the early numbers suggest Green is producing a lot like he did in Oklahoma City. And for the 2010-11 Celtics, that may not be good enough.

Green has played in 10 lineups that have logged at least 10 minutes together in Boston. The numbers, culled from Basketball Value:

Offense: 337 points scored in 305 possessions, or 110.5 points per 100 possessions. That’s a nice number for Boston, one that would rank just below the top five for the full season. Its offense ranks 18th overall.

Defense: 326 points allowed in 300 possessions, or 108.6 points allowed per 100 possessions. And here we see it happening again: Green’s team is playing far worse, defensively, with him on the floor. The sample size is small — only about 172 minutes — but the fact that we’re seeing this same trend repeat itself in Boston is not encouraging. The Celtics and Bulls have taken turns atop the league’s defensive rankings all season, with both surrendering about 100 points per 100 possessions. With Green on the floor, Boston has defended at about the level of the Nets and Rockets, who rank 20th and 21st in points allowed per possession, respectively.

Parse the numbers a bit more, and a second trend is repeating itself, one that might temper the bad news a bit: Most of this deluge of opponent scoring is coming when Boston plays Green at power forward. Considering only these 10 lineups, opponents have scored about 123 points per 100 possessions when Green is at the “4.” That number would embarrass the Raptors. The bad news: The  lineup in which Green has logged by far the most minutes features him at power forward alongside Boston’s core four of Rajon Rondo, Ray Allen, Paul Pierce and Kevin Garnett. This group has played 46 minutes together, triple the number of minutes Green has played with any other foursome.

The good news: Seven of these 10 lineups feature Green at small forward, and those lineups have done quite well defensively — about as well as Boston’s elite season-long number. Of course, Boston already has a pretty good small forward (Pierce) who figures to get a ton of minutes in the postseason. Rivers has paired Pierce with Green on the wing to shaky results, but the Green/Allen pairing has fared much better defensively. Perhaps there is promise in that wing duo.

Again: It’s worth nothing that Oklahoma’s defense struggled horribly when Green played power forward compared to when Green played small forward, and opposing power forwards regularly lit up the Thunder with Green on the floor at that spot. That was a bigger problem with the Thunder because Green was their starting power forward and played a much higher percentage of his minutes at that position in Oklahoma City than he will in Boston. Perhaps Green’s size disadvantage against power forwards is a bigger deal than his alleged quickness disadvantage against small forwards?

Of course, it’s too early to draw any conclusions about Green’s play and role in Boston, especially because we don’t know yet how Rivers will use him in the playoffs. But whereas nobody anticipated how well Denver would play post-’Melo, it seems Boston has gotten exactly the same Jeff Green the Thunder had: a tweener who can help your offense, will hurt your defense and won’t rebound at an acceptable level for his position. (His defensive rebounding rate in Boston just beats out Allen’s.)

The Celtics were likely hoping for more, and they’re going to need it.