Danny Ainge is happy with his class of rookies, but they have work to do to carve out a role

It was apparent during Tuesday's rookie introductory press conference that Boston Celtics president of basketball operations Danny Ainge is satisfied with his haul in the 2015 NBA Draft, despite his aspirations to trade up and make a splash.

Whether it's Terry Rozier's competiveness, R.J. Hunter's feel for the game, Jordan Mickey's versatility, or Marcus Thornton's athleticism, Ainge likes what he sees going forward. But these rookies will need to earn their stripes in summer league and training camp as they prepare for a rigorous slate of 82 regular season games.

"I always say that it's a player's job to prove to the coach that he needs you. And young players always start out at a disadvantage; they have to beat our veterans, typically, for playing time and for opportunities," Ainge said. "But it's each one of these guys' job to prove that Brad [Stevens] needs them. And their play this summer, it'll begin there, and their work leading up to the season and training camp, everything they do will be noted, their work ethic and their character and their performance and production."

Here are notable quotes from each of Boston's four draft picks, Ainge's thoughts on each player, and what they must accomplish to carve out a role in the rotation:

Terry Rozier, Louisville, Guard

What Danny Thinks: "I think Terry Rozier is a tremendous competitor. He's in the level of the Delonte [Wests], Tony Allens, Avery Bradleys, that level of competitor and athlete. Those are the things that we like about him."

What Terry Thinks: "I'd just say [I have] a winner's mentality. I'm not so worried about how many guards we've got. I'm just worried about how I can come in and fit for this team, fit for this league and help my team improve. That's what I'm more worried about."

Rozier is blocked on the depth chart by multiple guards, but if he's able to effectively facilitate offense, then he could earn a spot in the rotation. He's an extremely quick guard with great burst, and can get to the rim with ease, but he'll need to show he can do the little things. Defensively, he should have no issues making the transition to the NBA, though there is always an adjustment for young players, just like there was for Smart last season.

R.J. Hunter, Georgia State, Wing

What Danny Thinks: "R.J. has a great feel. He's a terrific shooter. He can shoot from anywhere in the gym and he can run pick-and-rolls, which is a big part of basketball nowadays. He's long, he can really pass the ball and he's a really skilled player...R.J. can play some 2 and 3, maybe someday can play some 1 and 2, because he's a ball handler."

What R.J. Thinks: "At this level you don't have to do a lot. They already have a playoff team, so I don't have to come in here and be superman, which is perfect for me. I just use my feel, use my shooting, use my IQ, and I can come in here and compete and I'll fit in."

Hunter has a lot of competition for minutes this season, including Avery Bradley, Evan Turner, and James Young, as well as every other guard due to the domino effect the depth has on the rest of the roster. In order to separate himself he'll first need to prove that his shooting can translate. Assuming it does, then he could earn some minutes similar to the role Gigi Datome received, but would give him a distinct advantage would be able to defend at his position. He showed good instincts playing zone at Georgia State, but will have a steep learning curve, both physically and mentally, playing man-to-man.

Jordan Mickey, LSU, Big

What Danny Thinks: "[Mickey] is a shot-blocker and an athlete that we desperately need in the frontcourt. He was the best athlete there, very long and athletic, and he can switch. It's a big thing having big guys that can protect the rim and switch and guard perimeter guys, and we think that Jordan can be one of those guys."

What Jordan Thinks: "I'm a player who starts with defense first. I led the country in blocked shots this year. I led my conference in rebounding. I think it's rare to find a guy who prides himself on defense."

Mickey does the little things well on both ends of the floor, but the signing of Amir Johnson suggests that he won't have much of a role this year. He's a terrific screener for his age, using a wide base to redirect defenders, and the open NBA floor could make him a pick-and-roll threat. But he'll need to show he can hit jumpers consistently from mid-range. On defense, he's physically capable of defending pick-and-rolls, but the mental aspect of the game, such as hitting his rotations or defending without fouling, needs improvements.

Marcus Thornton, William & Mary, Guard

What Danny Thinks: "Marcus is a jet. He's a lightning fast kid who can make shots."

What Marcus Thinks: "I'm a pretty good shooter, being able to stretch the floor. My abilities on the offensive end will be able to help contribute. It's good to see the league go that way. It's an opportunity for myself having a skillset that benefits in that way."

There's almost no chance Thornton is a difference-maker this this season, but that isn't necessary a bad thing for him. Thornton is William & Mary's all-time leading scorer, but needs to improve his pure point skills. Though he'll always be a score-first guard, developing his passing accuracy would help a great deal at the pro level. He also needs to learn how to use his elite athleticism on the defensive end to compensate for his average size. If he does, he could become a microwave scorer in the future.

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