6 Undrafted 2015 NBA Rookies with Greatest Potential to Make an Impact Next Year

Every year, we see a handful of prospects go overlooked during the NBA draft process.

Last season, it was Tarik Black, Langston Galloway and Bryce Cotton. The summer before, it was Matthew Dellavedova, who soon emerged as a key contributor on a title contender.

It's going to happen again in 2015-16. We've already seen a few undrafted players from June get picked up on partially guaranteed contracts. And some of those players happen to have landed in situations that may allow them to thrive. 

Based on college performance and summer league play, as well as their fit on the team they'll enter camp with (if they've already signed a contract), we've pegged six undrafted prospects to emerge as surprise impact rookies. 

Maurice Ndour, Dallas Mavericks, PF

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Summer League Averages: 9.6 PPG, 4.8 RPG, .512 FG%, 1.0 SPG, 2.0 BPG

Few players took better advantage of summer league than Maurice Ndour, who used it to find the radar and a contract with the Dallas Mavericks. 

He's ultimately come out of nowhere to emerge as a possible hustle-and-energy big man. 

Ndour played high school ball in Japan before spending two years in junior college and two more at Ohio. He then averaged 9.6 points and 4.8 rebounds with the Knicks in Las Vegas, where his motor, nose for the ball and promising touch stood out throughout the week.

Ndour, who shot 43.5 percent from three-point range and 78.5 percent from the free-throw line last season at Ohio, simply projects as one of those bigs who can make things happen without needing plays drawn up for him. 

Though the Mavericks have a handful of power forwards behind Dirk Nowitzki, none of them bring anything particularly unique or special to the table. In Dallas, Ndour's high activity level could potentially hold value to what's a fairly lifeless second unit, specifically up front. 

Alan Williams, Free Agent, PF/C

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Summer League Averages: 12.1 PPG, 7.7 RPG, 44.9 FG%, 0.3 BPG

One of the most productive players in the country at California Santa Barbara over the last three seasons, Alan Williams' lack of size and athleticism held him back in the NBA draft conversation. It didn't help he played most of his games against inferior competition in the Big West conference. 

But Williams' summer league showing has made him difficult to continue ignoring. He was an absolute monster, averaging 20.5 points and 11.8 rebounds over his final four games with the Rockets. 

Though only 6'8", Williams' 261-pound frame (NBA combine) can be a handful in the paint, where he uses his body to seal off defenders and his touch to finish over the shoulder. 

And while he does most of his work with his back to the basket, he did knock down 44.4 percent of his mid-range jumpers in 2014-15, per DraftExpress' Kyle Nelson, and 76.8 percent of his free throws. 

Still, it might be Williams' rebounding prowess that leads to a contract and rookie minutes. He pulled down 21 of them during his final game in Las Vegas after averaging in double digits as a sophomore, junior and senior.

"I'm just going to continue to work hard," Williams told CBS Sports' Sam Vecenie. "I'm extremely blessed to be in the position I'm in. I'm so humbled and grateful to the Houston Rockets organization to put me in this position right now. So whatever happens happens, and hopefully I can be playing in the NBA someday."

There is bound to be some team out there that views Williams as a Glen Davis-type of big man. He'll get a shot sooner or later.

Ryan Boatright, Brooklyn Nets, PG

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Summer League Averages: 14.1 PPG, 2.2 APG, 40.2 FG%, 43.1 3PT%

Ryan Boatright was a sneaky pickup for the Brooklyn Nets, who could actually use another playmaker. 

Undersized at just 6'0", Boatright never generated much draft buzz, but he compensates for a lack of height with ultra quickness and lights-out shooting range.

Last season at Connecticut, he hit 86 threes at a scorching 41.1 percent clip. And Boatright remained hot in summer league, hitting a whopping 22 triples on 43.1 percent shooting. 

He also averaged 14.1 points, showing he can stop and pop, use the floater or get to his spots as a driver.

Boatright doesn't quite project as a point guard you'd want to run your offense, but a role that allows him to play to his strengths—his ability to create and make shots—could help ignite Brooklyn's second unit.

T.J. McConnell, Philadelphia 76ers, PG

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Summer League Averages: 5.2 PPG, 3.3 APG, 35.9 FG%, 20.0 3PT%

T.J. McConnell will head to camp with the Philadelphia 76ers, where his defense and passing should help differentiate him from the slew of point guards he'll be competing with. 

Though not the greatest athlete, scorer or shooter, it's McConnell's toughness and ability to make teammates better that drives his appeal. He isn't going to wow fans with playmaking, but he can manage an offense, set the table and lock down opposing ball-handlers. 

Coaches are bound to value his in-your-face intensity, as well as his decision-making skills with the ball. 

The Sixers staff should also covet McConnell's leadership, something its lineup sorely lacks. 

He isn't quite the point guard of the future for Philadelphia, but he does have the potential to develop into one of its smaller long-term pieces. Look for McConnell to quickly become a fan favorite, as well as a rotation player in a backcourt that doesn't have much to offer. 

Jonathan Holmes, Free Agent, PF

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Summer League Averages: 10.0 PPG, 5.0 RPG, 48.1 FG%, 46.4 3PT%

Jonathan Holmes going undrafted remains one of the bigger mysteries of the summer. He offers an NBA-friendly blend of athleticism, size and shooting ability, as well as the defensive versatility to match up with both forward positions. 

Holmes played eight games with the Boston Celtics in summer league, where he averaged 10 points and five boards per game and hit a terrific 13 of 28 threes.

He looks the part of a Draymond Green-type of small-ball 4 who can stretch the floor, defend and provide an all-around physical presence.

According to Adam Himmelsbach of the Boston Globe, "a number of teams have expressed interest" in Holmes. Basketball writer Kevin O'Connor pegged Holmes as the one who'll get away from the Celtics, who are already deep at the 3 and 4. 

Someone is bound to pick up Holmes, who, after four years of sacrificing as a supporting cast member at Texas, should be ready and comfortable adjusting to a complementary NBA role. 

Duje Dukan, Sacramento Kings, PF

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Summer League Averages: 9.2 PPG, 2.4 RPG, 43.8 FG%, 41.7 3PT%

Having averaged fewer than five points per game in each of his four years at Wisconsin, Duje Dukan was never really a talking point in the NBA draft conversation. 

It didn't stop the Sacramento Kings from picking him up and fully guaranteeing his rookie year, according to Basketball Insiders' Eric Pincus. 

Clearly, the Kings have a plan for Dukan, who shot 41.7 percent from deep in summer league. And given Sacramento's lack of shooting in the frontcourt between Rudy Gay, DeMarcus Cousins and Willie Cauley-Stein, Dukan's ability to space the floor could lead to minutes in 2015-16. 

Whether he's talented enough to develop into anything special is debatable, but he already has one foot in the door in Sacramento, which is half the battle for a player just looking to make an NBA living. 

Assuming the coaching staff allows him to play to his strengths, Dukan could be a surprise contributor as a stretch 4 off the Kings' bench.