The most impressive part about Bryce Harper's career so far has arguably been his ability to consistently exceed expectations while being among the most-hyped prospects in baseball history.

Tales of his achievements across Las Vegas’ high school diamonds were already the stuff of legend when he cut his prep career short by two years to play a season of junior college baseball in preparation for the 2010 draft. Entering the spring as the overwhelming favorite to be the top pick, scouts would have been impressed if Harper merely held his own in a good conference that used wooden bats, but instead he re-wrote the College of Southern Nevada record book, hitting .443 and slugging 31 home runs to eclipse the school record by a mere 19.

Just 17 years old when signed to a record deal by the Nationals, Harper began his professional career in the Arizona Fall League, playing against and with upper-level prospects, many of whom had already reached the big leagues. After slugging .639 in limited play, one scout said, “He’s a child, and he not only belonged on the field with those guys, he stood out.”

His official career got off to a slow start in April, but a pair of contacts got him back on track, and heading into Tuesday night's action he was batting a whopping .346/.429/.627 for Low-A Hagerstown in the South Atlantic League. Harper has been intentionally walked five times in his last 22 games. That's nearly unheard of at this level; last year's season leader had six.

There is no statistical or scouting evidence to say the Harper is not good, or even not very good. But just how good can he be? To find out, let’s go through the traditional five tools and walk through the ranges a number of scouts projected for him as a big-leaguer on the 20-80 scale (with 50 being major-league average) based on early-season looks.

Hitting: 50-65
There is a somewhat wide range on Harper's ultimate ability, with this spectrum representing a .270-.300 hitter. He takes an enormous, violent swing, but at the same time, scouts are consistently surprised at how much contact he makes with it. While he's currently striking out once for every 4.4 at-bats, that's actually a promising number considering his age, and what was once an exaggerated front step that included a strange knee twist has been muted considerably. He's not going to win batting titles, but he's certainly not going to be a low-average, one-dimensional slugger, either.

Power: 80
“He's basically Superman.”
“It's freakish.”

The 20-80 scale is on a bell curve, so 80s are rare, but even more difficult is to find such a grade that scouts are universal on. There are plenty of big and strong teenagers out there, but finding one with the type of advanced, right-now ability to drive balls to all fields while adding the necessary loft and backspin forces scouts to dig deep for comparisons. “I don't think we've seen a high school player like this since Alex Rodriguez,” said one talent evaluator, referring to the Yankees third baseman who was the first overall pick when Harper was not yet eight months old. Before he was mashing 465-foot home runs in the big leagues, Mike Stanton was seen as the prospect most likely to hit 50 home runs in a single major-league season, and now Harper wears that crown.

Glove: 50-60
Harper was a catcher as an amateur, but moved immediately to the outfield after signing for a variety of reasons. Most importantly, he just wasn't a good receiver. While Harper’s bat could be ready for the big leagues before his 20th birthday, developing him into a big-league defender behind the plate could take an extra two or three seasons. In addition, having him catch is an injury risk and waste of his current athleticism, and would relegate him to the bench for 20-plus games per year to rest. Harper has taken well to the outfield, even playing center field on occasion. While there are some improvements needed in his reads and routes, scouts believe he'll end up a good right fielder. “What impressed me so much is that he's clearly working hard to improve out there, and you don't always see that in kids that are special hitters,” said one scout.

Arm: 70-80
One of the reasons Harper was a catcher was that his arm was such a weapon. He pitched in the low 90s as an amateur, and he has already racked up four outfield assists. With strength, carry, and accuracy, big-league baserunners will be hesitant when looking for the extra base on balls hit his way.

Speed: 30-50
While speed is the least-important part of Harper's game, a discussion of how it projects down the road delves deeper into the projected final product. He's plenty fast now, showing times from home to first that are consistently a tick above average, and he has stolen seven bases in 10 attempts so far.

“I think that when he comes up, he could steal 15-20 bases per year,” said one scout.

The real debate concerns what he will look like physically by the time he is in his late 20s. Already 6-foot-3 and 225 pounds, Harper is a massive human being for an 18-year-old and not done filling out, leaving some scouts to fear that by the time he has matured, he'll be a 250-pound beast more in the mold of a massive first baseman as opposed to a multi-tooled outfielder. Such growth would certainly limit him at the very least to an outfield corner, but it could also affect his offensive numbers in other ways, as reduced speed means fewer singles, doubles, and triples.

“I'm still not sure what he's going to be in the end, other than a really good hitter,” said another scout. “He's could be this superstar who could beat you in a bunch of ways, but if he keeps growing, he could end up being a big, slow first baseman who reminds one physically of Ryan Howard.”

There is no score for makeup, but it still needs to be discussed. While it never came close to outweighing his talent, Harper's arrogant, confrontational style of play turned off many during his high school and college years. He has yet to really temper his style as a pro, which has already led to a couple of near-brawls due to a propensity to stare down opposing pitchers or gesticulate toward dugouts.

“It's seems to happen every night, and it might not change until he gets to the big leagues where teammates won't put up with those antics,” said a team executive. “Then again, maybe he'll hit four home runs in his first week and everyone will shut up.”

The Verdict
While Nationals general manager Mike Rizzo has already clearly expressed that Harper will spend all of the 2011 season in the minors, reaching the big leagues as a teenager is still a distinct possibility; he could get called up by the end of the 2012 season. In the last quarter century, only 12 position players have reached the majors before their 20thbirthday, and those 12 have combined for 51 All-Star game appearances, four MVP awards, and another 24 top-10 finishes in the voting. It takes a special talent just to get there so quickly, and Harper is going to likely do just that. Don't bet against him continuing to exceed the expectations that really couldn't get any higher.

                           A version of this story originally appeared on ESPN Insider Insider.