Jeff Green hasn't found his way yet

So here it is: Jeff Green's opportunity to be truly welcomed into the fold.

Since the wildly popular Kendrick Perkins was shipped to Oklahoma City at the trading deadline, discerning New Englanders have stood stiffly with their arms folded and lips pursed waiting for proof that Green's presence enhances the Boston Celtics' chances of still being "championship driven."

The evidence has been spotty. Green hasn't been horrible, nor has he been electric. Initially, he appeared alternately confused and overwhelmed, yet displayed moments in the opening playoff round against the New York Knicks when he exhibited glimmers that validate the value of the trade: an aggressive run at the rim, solid minutes bodying Carmelo Anthony while Paul Pierce earned a respite, a rebound in traffic when he elevated and displayed his athleticism.

His teammates contend Green has grown more comfortable with his role in the past two weeks. He was a starter averaging 37 minutes a night with the Oklahoma City Thunder and has been asked to adapt to coming off the bench to spell two future Hall of Famers, as well as morph into the go-to guy when the reserves are assembled together on the floor.

He was clearly pressing earlier in the season to generate some scoring. A lack of any significant practice time forced him to learn the Celtics' offensive sets on the fly. Now, with a full week to prepare for an almost certain date with the Miami Heat, that excuse will be moot.

Doc Rivers claimed on Saturday he believes Green is "coming on," but we'll know if Rivers means it when we see how many minutes he metes out to his multi-purpose forward in the next series. Green averaged 23.5 minutes a game in the regular season with Boston, but saw that drop to 16.8 minutes a game in the Knicks series. Rivers acknowledged the bench players, Glen "Big Baby" Davis and Green in particular, were under pressure to perform at a higher level.

"The second unit knows there's a certain point when we're up by 12 or 14 and the score starts dwindling, they all may come out," Rivers said. "They're looking up and thinking, 'Oh crap, somebody better play well in this group.' I'm sure that doesn't help."

Perhaps expectations are part of the problem. Although Green averaged more than 15 points a game for Oklahoma City, that was never the blueprint here. Boston acquired him to provide Rivers with versatile lineups that allow Boston to go big or small, which helped them win the championship in 2008 with Perkins on the pine in crunch time.

Green is not a shutdown defender, but the idea was he could provide key minutes at multiple positions. By trading away Perkins, his physical, defensive-minded center, Celtics boss Danny Ainge gambled that with just one true dominating big man in the East (Dwight Howard) who Boston might not even face in the postseason, the more pressing need was perimeter defensive help for Paul Pierce and Ray Allen for players … just … like … LeBron James.

Pierce was so exhausted from chasing the King from pillar to post last season that he ran out of gas in the NBA Finals, when he was charged with containing Kobe Bryant in addition to carrying the primary offensive load.

With Tony Allen (gulp) proving to be a bigger loss than anticipated, Jeff Green must fill that void. Gritty defense earns minutes with Rivers. Green was overaggressive in guarding Anthony at times, but insisted, "I can't worry about fouls. I've got to establish position regardless."

While Green's perceived offensive shortcomings continue to be dissected, he has demonstrated good ball-handling skills and adept passing vision. He is a decent shooter and moves well without the ball; in fact, Ainge argues he's the most effective cutter in the front court.

For all his struggles, Green still managed to average 9.8 points and 3.3 rebounds a game in his 26 regular-season games with Boston.

In short, Green remains the most skilled player in the transaction with Oklahoma City.

Ah, but does that make him the best player? The ongoing vigil for Perkins is understandable. He was a hard-working, intimidating, emotional leader who was beloved by almost everyone. Whether that offset his standing as an offensive liability remains to be seen.

Perkins' trademark scowl and forearm shiver played well in these parts. The blank "nobody's home" facade of Green isn't quite as enticing to a sports city that adores Terry O'Reilly almost as much as Bobby Orr.

Green knows his demeanor is a topic of discussion.

"I used to get that in Oklahoma City," Green said. "It's something I developed in college. There are times when you don't want to put too much added pressure on yourself. It becomes important this time of year to be really focused, to be calm. I think [my demeanor] helps me."

"There's great value in that," Ainge agreed. "I know from my own career as I matured, I needed to calm down, to control some of that passion.

"It takes all types. Some players who don't come in crazy ready when the game is going a thousand miles an hour end up with the ideal energy level in that situation."

Green shot just 33 percent against a flawed Knicks defense en route to submitting 6 points and 3.5 rebounds a night. Teammate Delonte West described the entire second unit in the series as "pedestrian."

Ainge maintains because of the firepower of the "big four," scoring opportunities for the second unit may be fleeting. Pierce and Allen figure to log heavy minutes as the Celtics advance, so Green's minutes might also be limited.

"First of all, I don't know if he's frustrated, but I know we're asking him to assume a much harder role," Ainge said. "Jeff isn't just coming off the bench, he's coming off behind Ray and Paul, and when those guys are playing like they're playing there won't be that many opportunities.

"Then Jeff might find himself out there with [Kevin Garnett] and [Rajon] Rondo, so again, it might be hard for him to make contributions by scoring, which is how the fans and the media measure things.

"We can't judge our bench by our stat line. You have to judge them by holding their own. Our starters are our team. They're going to carry us.

"We know Baby, Delonte and Green are good players. If Jeff Green doesn't score 12 points, big deal."

The big deal will be how Green plays against the upstart Heat, with their nicknames and their fireworks and their South Beach talents.

If Jeff Green has anything to do with sending LeBron and the boys packing, the discerning fans' stiff arms won't be folded anymore. New England will embrace him as one of its own.

But, if it goes the other way, the poker-faced forward better be ready.

Those pursed lips know how to boo, too.

Jackie MacMullan, who has spent nearly 20 years as a beat writer and columnist in Boston, is a columnist for ESPNBoston.com.