Welcome to numberFire's Rookie Power Rankings. All year we're going to be looking at which rookies have performed the best. Bear in mind, this isn't a Rookie of the Year watch.

We've seen from previous years that Rookie of the Year is heavily based off of minutes played and points scored. While Andrew Wiggins won Rookie of the Year last season, advanced metrics strongly disagreed that he was the best rookie.

So instead we're going to use our nERD metric to evaluate which rookies have been the best for their teams so far this season. nERD indicates how many wins above or below .500 a player would make an average team over a full season. It's like Win Shares but is meant to be predictive rather than descriptive.

Because it so early in the season, we are going to limit our consideration to players who have averaged at least 15 minutes per game. 

Few things in the NBA are as exciting as a new rookie class. And two weeks into the NBA season, the rookies have impressed. Let's take a look at who's been best.

5. Myles Turner

nERD: 1.0

Myles Turner slides in at number five on our list. The power forward has yet to play major minutes for the Pacers, but he still makes our cut off with 18 minutes per game. Turner is averaging 7 points and 3.3 rebounds per game while shooting 55 percent from the floor. Over three-fourths of the 6-foot-11 Turner's shots have been two-pointers from beyond 10 feet. And he's been successful with those mid-range shots so far this season, making about 52 percent of such shots. Turner has also avoided turnovers this season, averaging 0.9 per game, the third fewest among qualified rookies.

He hasn't stuffed the stat sheet or made too many highlights, but his efficient and relatively mistake-free play is helping the Pacers win. 

4. Kristaps Porzingis

nERD: 3.3

Coming in at fourth is New York Knicks power forward Kristaps Porzingis. Booed when he was drafted, Pozingis has performed much better than most expected early in his NBA career. He made a splash in his first game by outscoring Carmelo Anthony, and through his team's first seven games, he's started every contest and is averaging 12.3 points per game. He has struggled shooting, connecting on less than 40 percent of his shots. Billed as a three-point threat, Porzingis hasn't lived up to the hype from behind the arc. He's sunk 5 of his 22 attempts from three-point land. Porzingis, though, is still second on the team in points and field goals attempted.

Despite the efficiency struggles, Porzingis has found ways to make an impact for the Knicks. Overall, Porzingis has put up 8.6 rebounds per game, second for rookies. The 7-foot-3 center is also averaging 3.6 offensive rebounds per game, best among rookies and fifth in the entire NBA. He's made highlight reels again, again and again for ridiculous putback dunks. Pegged as a long-term project, Porzingis' early success has got to have Knicks fans excited.

3. Willie Cauley-Stein

nERD: 4.1

While the rest of the players on our list are members of teams that are performing relatively well to start the season, the Kings have struggled mightily. But Cauley-Stein has made the most of it, putting up 6.6 points and 5.9 rebounds per game. Predictably, he's doing it at an incredibly efficient rate, shooting 71 percent from the field. Also predictably, the center has taken 61 percent of his shots from within 3 feet of the basket. He has taken exactly one shot from beyond 10 feet (he missed). On those shots close to the rim, Cauley-Stein has made almost 80 percent of them.

Thanks to his ridiculous efficiency to start the season, Cauley-Stein has a 129 Offensive Rating, according to Basketball-Reference, which places him sixth among players with at least 100 minutes played this season. Defensively, Cauley-Stein hasn't performed as well as the Kings may have hoped when they drafted him fifth overall this year, but he's still done pretty well, averaging about a block and steal per game to go along with a Defensive Rating of 105.

Among all rookies who have played at least 15 minutes per game this season, Cauley-Stein is last in Usage Rate. If the Kings feature him more in the offense, we may be seeing more of him in our power rankings

2. Nemanja Bjelica

nERD: 4.2

If your reaction to this was "who?" you're not alone. Bjelica is the Timberwolves' 28-year-old rookie. We've looked at his stats in the Euro League previously, and so far he's done a pretty good job of carrying the success he found in Europe to the United States. The Serbian power forward was drafted in 2010 and only made his debut this year.

In 29 minutes per games this season, Bjelica is averaging 8.2 points, good for sixth among rookies. Bjelica is also third among rookies in rebounds per game and, strangely enough, fifth in assists per game, ahead of this guy. Bjelica's been efficient, converting 48.5 percent of his shots. He's shown he can make shots from long range too, shooting over 40 percent from deep. With his 60 percent Effective Field Goal Percentage, Bjelica ranks second among rookies playing at least 15 minutes per game. One thing to note is that he hasn't missed a shot within three feet from the basket so far. That screams unsustainable, so it's likely that we'll see his scoring numbers drop off. 

But for now, let's let Professor Big Shots have his time to shine

1. Karl-Anthony Towns

nERD: 6.2

The first overall pick from the 2015 Draft earns the number one spot in our inaugural rankings. Towns has started each of Minnesota's games and is averaging just under 30 minutes per game. He's averaging 15.5 points and 10 rebounds per game so far, the only rookie averaging a double-double. His early season success has put him in elite company. If he could sustain a double-double through the whole season, he'd join Blake Griffin as the only rookies to do so in the past 10 years. Along with Bjelica, Towns has helped his Timberwolves win four of their first seven games, a quarter of their win total from last year. 

Towns has played stellar defense so far for the Timberwolves, one of last year's worst teams defensively. Minnesota ranked last in opponent points game last season. This year, the Timberwolves are in the top 10. Towns is averaging three blocks per game, fourth in the NBA. Among all players who have played in at least 100 minutes this season, Towns ranks fifth in Defensive Box Plus Minus. 

His solid offense and impactful defense through two weeks of the season make Towns the obvious choice for first on our power rankings. Will he keep it up? Check back in two weeks to find out.