Danny Ainge's selection of Terry Rozier with the 16th pick in the 2015 NBA Draft took practically every Boston Celtics fan by surprise, so much so that they were blinded to see that the Louisville guard is actually the type of player they have a habit of falling in love with.

"He's really athletic and really tough and I love those kind of guys," Ainge said on draft night. "I think our team will love him. I think our fans will love him. I think he has a great upside as a two-way player."

It won't take more than one summer league game for Rozier to remind Celtics fans of Marcus Smart or Avery Bradley on defense. At 6'2" with good size, Rozier has excellent lateral quickness and the strength to guard larger players. He grinds, hustles for loose balls and rebounds, and plays with an edge.

Here's Rozier causing a turnover by being his pesky-self using his long 6'8" wingspan:

But it's Rozier's knack for making these types of plays in clutch moments that'll win fans over, much like Smart did last season. Here he is forcing a turnover in the final seconds of Louisville's NCAA Tournament win over UC Irvine:

"He's a basketball player who wins and impacts winning," said coach Brad Stevens. "The one thing that was consistent when talking to people around him, whether it was coaches, assistant coaches, players, managers, is that the kid studies and works as much as anybody. I think that's a huge quality. He wants to be really good."

It's not hard for Rozier to find the motivation to succeed because of his upbringing. His mother and grandmother raised him in dangerous areas of Ohio, and his father has served two separate prison sentences throughout Rozier's life. He is currently serving a 12-year prison sentence for his role in a robbery and kidnapping in 2003, and is schedule for release in 2018.

But Rozier has learned a valuable lesson from his father: work hard and don't end up like me.

"I don't want to end up in his shoes," Rozier said in 2011. "His life is not over, but I don't want to end up like him where I put myself in a bad spot to get locked up."

Rozier has used this motivation to develop a strong work ethic in the gym and the weight room. He was just a lanky kid in high school, but quickly added muscle to become the stalky player that'll grace the parquet floor this season. He spends extensive time watching film of his favorite player, Dwyane Wade, who he tries to resemble on the floor.

"Terry has mimicked D-Wade so much I think sometimes he thinks he is," said Louisville head coach Rick Pitino.

That confident mindset works both for and against Rozier, since his risk-taking allows him to make breathtaking winning plays, but also leads to many frustrating mistakes.

"The biggest thing is he just has that burst," Stevens said. "He's got that burst that the really good point guards have."

Rozier is a downhill pick-and-roll playmaker who uses his speed to his advantage. The ball doesn't slow him down and he's very good at splitting screens like he does in the video above. He showed flashes of using different speeds towards the latter part of his sophomore season at Louisville, though he must incorporate chance of pace more consistently in the NBA.

But Rozier lives in the paint and can penetrate with ease using a plethora of aggressive, speedy moves like crossovers and inside-out dribbles. He's the only player on Boston's roster other than Isaiah Thomas who doesn't require a screen to get into the teeth of the defense.

Rozier does a good job of incorporating a floater that has potential. This could be a valuable tool for him in the NBA, and it's often what separates average scorers from the good ones, since it's a creative tool for smaller scorers to use.

But he is a poor finisher at the rim, largely due to his inability to finish with his left hand and his subpar shot selection. He'd force plays that he had no business even attempting, but he likely wouldn't have been inclined to make those types of plays as frequently as he did if Louisville had better spacing and more scorers.

The Cardinals shot 30.4 percent from three last season, which ranked 315 of 351. That's like how Thomas had to put the Celtics on his back against Cleveland. But without a secondary scorer on the floor to help him, he was unable to get anything going offensively. The entire season was much like that for Rozier.

"[Louisville] didn't shoot it like some of his teams in the past, so obviously that's going to clog the lane," Stevens said. "But he's still getting there almost every time he drives it. He's got a real good burst and real good body control. He has to get better at finishing with a variety of finishes, but we saw a bunch of those in one-on-one segments and workouts."

The wider spacing the NBA floor naturally provides should help him get better angles driving to the bucket, but he still has flashed the ability to make plays for his teammates even if lanes aren't there, like he does in the two clips above. He loves using a hop step to snake into the teeth of the defense and on the assist to Montrezl Harrell, he uses a nice hesitation move to put the defender on skates.

With a 1.7 assist-turnover ratio, he isn't always the most willing passer, and his feel for the game is below average, but the Celtics probably feel confident that he'll be able to improve in this area due to the system that'll influence him. Stevens was highly successful in getting a similarly raw point guard in Smart to improve his decision-making this past season, which bodes well for Rozier.

But that wouldn't matter if he weren't willing to accept this level of instruction, which is where his work ethic comes into play.

"I really feel like it was my fault [we lost in the Elite 8]," Rozier told the Courier-Journal. "[I was] pressing too much, trying to do too much, not letting the game come to me, being that competitor who wanted to win so bad - I just feel like I overdid it. We came up short mainly because of me. I was hurt after that game. I was hurt. It hit me out of nowhere. I said to [my teammate], 'I feel like it's my fault.' I just busted out crying. It was just a lot, man. It was a lot."

This self-doubting attitude could work to his advantage in Boston. Combined with the instruction of Stevens and an ability to admit when he's at fault could lead to an increased level of accountability and therefore better decision-making on the court.

Stevens can get creative using Rozier off-ball. Though he shot only 30.6 percent from three, he's a solid standstill spot up shooter that uses the hop to get his shots off quickly. This will allow him to play on the court with Smart or Thomas.

Rozier's ability to shoot off the catch also gives him potential off screens. With his speed, he can race through screens to get open, though he lacks experience in that play type. He was used more frequently in dribble handoffs, which he excelled at.

Overall, Rozier has very good shooting mechanics to build on. Having poor-to-average shooters "get more reps" as a means of sparking improvement is a road to nowhere, like it may have been for Phil Pressey, but "more reps" might be all Rozier really needs. He uses the turn, the sweep and sway, and the dip to effectively shoot from deep. Simply getting his landing narrower should improve his percentages off the catch.

However, the Celtics must also diagnose a problem with his release. He misses "left" and "right" as opposed to just "short" and "long," which suggests there could be a mechanical problem with his fingers or wrist. Once that's diagnosed, it must be corrected. It's possible this problem is related to his unbalanced landing.

Rozier needs to improve his shot off the dribble, but he is solid from mid-range. He's capable of pulling up out of the pick-and-roll, as displayed above in that sensational Wade-like weave through the defense into the jumper, but he hasn't shown he can make defenders pay for going under screens by draining threes over a screen. Developing this would add a new dimension to his game, but it doesn't appear to be something he'll utilize as a rookie.

Boston's roster is currently unbalanced; they have six "primary ball handlers" and need to trim that number down. But it's too early in the summer to discuss what level of opportunity Rozier could receive this season. Free agency has yet to begin and the roster could look dramatically different in just a few weeks.

The bottom-line is the Boston Celtics drafted a player they believe had the highest upside of the options available. While it remains to be seen how he fits into the team's plans this season and in the future, he is undoubtedly a talented two-player in a promising situation that could help him develop rapidly. It might not even be long before fans are clamoring for Terry Rozier to get more playing time.

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