Despite only just turning 19 last month, Isaiah Hartenstein has been on the radar screen for quite some time. The son of former Oregon standout and long-time pro in Germany, Florian Hartenstein, Isaiah was born in Eugene and emerged as a prospect very early on, averaging 11 points and 4.1 rebounds per game playing up years in the German JBBL all the way back in 2012 at the age of 13. Hartenstein introduced himself to NBA scouts at the 2014 FIBA U16 European Championship, where he averaged 10.3, 9.3 rebounds, and 1.9 assists over 26.1 minutes per game playing alongside an ultra-talented German 1998 generation.
Spending his junior career with the Artland Dragons, Hartenstein made his debut in the BBL in February of 2015, but it wasn't until last season that Hartenstein began seeing regular playing time for Artland's senior team, which by then had been relegated to the German Third Division due to financial woes. Spending the beginning of the 2015-2016 season on loan in Germany, averaging 11.6 points and 8.9 rebounds per game after signing a contract that summer with Zalgiris Kaunas, the young forward was summoned back to Lithuania in January of 2016.
Averaging 23.5 points and 11.3 rebounds per game at the adidas Next Generation Tournament for the historic Lithuanian club, Hartenstein turned in one of the top performances in the long history of that event. Seeing limited minutes in a small reserve role this season, Hartenstein showed well at times in the Lithuanian First Division (LKL), amid sporadic appearances in mop-up duty in the Euroleague, finishing the year averaging 4.2 points and 3.3 rebounds over 11.5 minutes per game for the Lithuanian champions, while also appearing in the FIBA U18 European Championship and the Nike Hoop Summit.
Hartenstein has a tremendous frame for a young big man, standing a massive 7'1.25 in shoes. Though he isn't particularly long, his 7'2.25 wingspan is still solid for a big man. Tipping the scales at 250 ponds, the 19-year-old made quite a bit of progress with his body during his time with Zalgiris, getting in better shape with the help of a professional strength and conditioning program. A fluid and mobile, but not overly quick or explosive athlete, Hartenstein has the skill-level to play some power forward, the size and strength to slide to the center spot, the ability to play above the rim on the move, and some potential to switch certain actions defensively, giving him intriguing versatility in today's NBA game.
Offensively, Hartenstien has a number of tools in his arsenal that could be polished into effective weapons down the road. His size and mobility make him a nice target crashing the rim in the half court or rim running in transition. The lefty also shows some craftiness inside, scoring with floaters and deft touch, and can step out to the perimeter and hit the occasional jump shot or attack closeouts. Also a fairly gifted passer, flashing terrific vision in spurts, Hartenstein has plenty of potential to grow into on the offensive and could grow into a very versatile big man down the road.
For all the many areas in which Hartenstein shows flashes, he still has a long way to go to reach his potential, as he isn't overwhelmingly consistent in any one facet at this stage. He struggles to finish over length, and is fairly left hand dominant, but still shot a serviceable 59% in finishing situations in the half court this season in his first experience against quality competition. Not possessing great explosiveness in a crowd, Hartenstein will face a steep jump in level of play as he moves to the NBA.
Away from the basket, Hartenstein made just 28% of his jump shots in the half court this season. He often shoots the ball with a bit of side spin and though he could theoretically provide some amount of floor spacing and value in pick and pop situations down the road, he's still a long way from being a reliable perimeter threat, and may need to tweak his mechanics to get there.
Though he has some strong moments as a passer, the young big man's decision-making and shot selection still leave something to be desired. Looking tentative from the perimeter at times, leading to travel violations, and lacking much shiftiness with the ball outside of some basic spin moves, Hartenstein isn't particularly adept and picking and choose his spots off the dribble, sometimes driving into traffic wildly and throwing up low percentage shots.
Defensively, Hartenstein shows some flashes of ability using his size and strength inside, and even moving his feet well against smaller players on the perimeter, but like most young big men, tends to be quite foul prone, finds himself in no-man's land from time to time, and is still figuring out how to make the most of his tools consistently. Lacking a degree of length, Hartenstein may never be a dynamic rim protector, but he certainly has the tools to be a capable individual defender, as he's competitive with a solid feel for the game and a strong frame. That shows up most vividly on the glass, where Hartenstein has always been a very strong rebounder (13.7 per-40 career in 61 games), pursuing loose balls with purpose instinctually.
Struggling at times with his body language, Isaiah Hartenstein puts a lot of pressure on himself, is outwardly expressive, and has yet to find the comfort zone needed in highly-scouted environments to fully show NBA teams to extent of his talent, Having a hard time keeping his emotions in check earlier in his career, Hartenstein has improved in that regard quite a bit as he's matured, but still has some lapses. Seeming to lose confidence at times, it is easy to forget that Hartenstein has just one season of high level basketball under his belt given how long his name has been on the NBA radar, and given his lack of experience, the signs of maturation he's shown this season are encouraging.
Among the more interesting international prospects available in this draft, Hartenstein seems like a solid bet to hear his name called in the first round on draft night, even if he isn't going into June with the type of momentum you might hope for after a ho-hum Hoop Summit experience and a season at Zalgiris in which he barely got a chance to show himself. The dearth of big men in this draft and question marks about exactly what he hangs his hat on has made it difficult for him to get his stock off the ground. Among the younger players in our top-100, it isn't clear what kind of niche the promising German talent will fill long-term at the NBA level, but he has a strong foundation of skills that could allow him to grow into a productive player down the road with the right support and development structure, and has some definite potential to grow into.