Despite having the NBA's third-best defensive rating, the Boston Celtics' most promising development might be taking place in Portland, Maine. That's where Jordan Mickey is taking advantage of his opportunity with the Red Claws by rapidly progressing into a two-way player seldom found in the NBA.

Mickey blocked over 100 shots in both of his seasons at LSU, and his potential as a versatile rim protector explains why Brad Stevens was "really surprised" he fell to the No. 33 pick in the 2015 NBA Draft.

But Mickey was still considered a project on offense as an inconsistent mid-range shooter. However, through 7 games with the Red Claws, Mickey is shooting 78.3% from the free throw line, and 41.7% from deep on 12 attempts. It's not about the stats though, because Mickey's shot mechanics have been overhauled, and that's the best indicator of his progress on the offensive end.

"I went back and looked at my shot and I noticed that my elbow was a lot higher than it should be, and it caused me to not have enough lift on my shot," Mickey told CelticsBlog, citing Fess Irvin as his pre-draft trainer. "Through the draft process, it was just something I worked on to try and lower my elbow so I could have more lift, and not have to strain to shoot a three or anything like that."

Mickey first flashed his improved mechanics at the NBA Pre-Draft Combine in May, but it wasn't a guarantee he'd extend his range to the three-point line. In any case, the hitch on his release was gone, and he wasn't shooting "on the way down" anymore, which were both issues at LSU.

Here, Mickey hovers in the air for a moment before releasing his shot, which likely caused him to fling the ball too much with his arms, instead of generating power from his legs. Below is the new-and-improved Mickey, who releases the ball at the climax of his motion while jumping slightly further ahead.

Most great shooters with range sweep their legs forward, while their upper body sways back. This reduces "strain" on the shoulders, as Mickey alluded to when referencing his elbow positioning, and it increases range, since more power comes from the lower body.

Many of these mechanical changes came after arriving at training camp, where Celtics assistant coach Kenny Graves helped further Mickey's development. Playing in Maine, under the NBADL's 2014-15 Coach of the Year, Scott Morrison, has given Mickey the opportunity to implement these changes on the floor.

"He has a good approach to his opportunity for development while in Maine and is making the most of it," Red Claws head coach Scott Morrison told CelticsBlog. "He is benefitting from extra reps and our confidence in him to stretch the floor when the situation presents itself. His results have been encouraging. And we will keep trying to improve his consistency from range while he is with us."

Every rookie would prefer to receive minutes in the NBA, but Mickey says he's looking at his chance with the Red Claws as a positive.

"Being able to go down there and work on some things that I might not get the chance to work on here is a good thing," Mickey said. "It's about making it through those mistakes and trying learning new things. Coaches and everyone else just said to take the opportunity to get better, and not look at it as a bad thing."

Morrison's Red Claws currently lead the D-League in tried threes per possession, which provides Mickey chances to spread the floor, especially in the screen game.

As a sophomore at LSU, Mickey began to develop a mid-range face-up game. But being able to knock down shots like the one above opens up new dimensions.

"It definitely helps [driving to the rim] when guys will have to respect that shot now, you know? They have to respect me from the three," Mickey explained. "Being able to knock a few down, guys have to be able to respect it, and that opens things up for myself, and being able to get the ball to my teammates in good positions."

Here, Mickey pump fakes and hurries by the defender for a layup. At LSU, Mickey showed the ability to dunk through contact, so it shouldn't be an issue for him to finish or draw a foul when a rim protector is lurking.

Mickey's fluidity is evident above, as it takes him only two dribbles and a spin to get into the teeth of the defense for a layup. That level of body control made him a menace rolling to the rim off screens at LSU, and it could someday translate into driving closeouts as a floor stretching big with the Celtics.

"Coaches said they want me to extend my range to the three-point line, because that's the way the game is going. A lot of fours are able to shoot that ball now, so it's something I have to work on," Mickey said, adding that Boston's clearly defined expectations have helped him "know what I have to do to be on the floor and to be a good player."

If Mickey's sustains his success as a shooter, it completely changes his outlook as a pro; no longer is he just a defensive-oriented big who contributes in the screen game on offense.

Perhaps, Mickey will evolve into than that. If he does, it makes him a rarity, because there are only so many players in the league that can protect the rim and shoot threes. There's Serge Ibaka, Al Horford, and Anthony Davis, and rookies Karl-Anthony Towns and Kristaps Porzingis.

But there's only one player in the NBA who's also capable of protecting the rim as a center, draining threes, and switching pick-and-rolls to lock down smaller scorers: Draymond Green.

Mickey is stoic, unlike the boisterous Green, and he hasn't displayed the same type of passing ability as the Warriors superstar. But the rest of the ingredients are there for him to be a similarly rare player. Mickey says, "Coaches also want to see me switch off and guard threes, twos. They just don't want to see me guard guys in the paint."

It's clear the Celtics want Mickey to be more than just a rim protector.

Morrison adds, "One of the things that coach Brad Stevens wanted us to work on with Jordan is guarding smaller forwards on the perimeter. Since Jordan is a great rim protector it is sometimes difficult to find situations for him to defend smaller players. But we have been able to have him showcase those skills through periodic switches and in some cases, guarding smaller scoring threats. Like everyone, he has some work to do, but he has without question shown an ability to move his feet and stay solid against smaller players, thus enabling him to utilize his length and shot contesting ability to make it difficult for players of different positions to score against him."

LSU typically hedged on most pick-and-rolls, and Mickey did a great job in that style of defense. With Boston and Maine, he usually "ices," which means he drops to the paint. As Morrison alluded to, Mickey mostly protects the rim for the Red Claws, and he currently leads the D-League with 31 blocks, but throughout his career he's established that he can contain smaller players.

Mickey isn't very tall, at just 6-foot-8. It's his massive 7-foot-3 wingspan and quick leaping ability that enable him to protect the rim, but he has the height and versatility of a forward. In the clip above, he switches onto a guard and does a good job of moving his feet while contesting the shot.

But even when Mickey's beat, he's capable of using his long wingspan to contest or block shots, like he does below.

The Celtics like to switch as much as possible, especially with their superb "small ball" lineups. But rebounding and rim protection are usually sacrificed when teams go small. And three-point shooting is out of the equation for most shot blockers.

But already, Mickey's three-point shot looks promising.

And there's little doubt that Mickey's shot blocking will translate.

Maybe Mickey eventually covers all those bases, if he successfully develops the ability to switch on defense, and his fundamentals improve.

It's even possible that Jordan Mickey is being harvested in Maine as the quintessential small ball center in the modern NBA.

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