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Bryce Harper – Best Prospect Ever?

Bryce Harper has received his fair share of attention over the years, coming as close to being labeled a prodigy as anyone in recent history. As a sophomore in high school, he was launching 500 foot home runs in Major League Stadiums. At 16 years old, Sports Illustrated put him on the cover of their magazine. At 17, he left high school a year early to compete with wood bats against Junior College players and hit 31 home runs, breaking the previous school record for homers in a season… which was 12. He also won the Golden Spikes award as the best amateur player in the country during the year in which he should have been a Junior in High School, and then was the first overall pick in the draft last summer.

And yet, despite all the hype, I’m still not sure we’re accurately appreciating just how good this kid really could be. He’s 18 years old, playing in his first professional season at a time when he should be getting ready to graduate from high school, and he’s hitting .396/.472/.712. That’s his line after last night’s 4 for 5 performance – one which included a grand slam, his eighth home run of the season.

He’s eighteen years old. Sure, it’s only 111 at-bats, but he could go into a slump of epic proportions and still match the numbers put up by some of the best age-18 seasons of all time.

For instance, in 1994, Alex Rodriguez was in a similar situation to Harper, having been the first pick in the draft the summer prior and making his debut in a full-season league at 18. He started out at low-A Appelton, where he hit .312/.376/.577 in 278 trips to the plate before he got promoted. Even after you account for the slightly lower offensive environment of the Midwest League in 1994 (average OPS of .710 versus .737 for the 2011 South Atlantic League), Harper’s performance is blowing away what Rodriguez did in Appleton.

He’s not only showing more power than Rodriguez did at the same age, but is also showing a more disciplined approach at the plate – something you just don’t find in many teenagers. Harper’s walk rate is the 14th best in the league and most of the guys ahead of him are in their twenties. Additionally, Harper is showing no real platoon split, posting an OPS better than 1.000 against lefties and righties alike. Even the best left-handed hitting prospects usually have problems with southpaws early in their pro careers and have to adapt to facing quality stuff from that side, which isn’t common at the amateur level. Harper is just mashing LHPs as well.

Rodriguez’s stock only continued to improve after he got promoted, as he hit well in both Double-A and Triple-A and finished his first big league season in the majors. Harper hasn’t done that yet, and he’s not a shortstop, so there’s a case to be made that the 1994 version of Rodriguez was a better prospect than Harper is now, but we have to at least acknowledge that Harper hasn’t had the chance to prove that he can do what A-Rod did during the summer of his first pro season, and Harper is easily outpacing him through this same point of their first season.

It’s not just A-Rod he’s showing up either – it’s basically every other prospect in recent history. Chipper Jones hit .326/.407/.519 in the same league back in 1991, but he was 19-years-old and had made his professional debut in rookie ball the year before. Andruw Jones played in the SAL at age 18, but hit a relatively modest .277/.377/.512 by comparison – his monster season would come the next year, when he climbed four levels and got to the majors after proving he was the game’s premier prospect.

Perhaps the most impressive young performance in the SAL over the last 20 years came from Adrian Beltre, who hit .307/.406/.586 in 288 plate appearances as a 17-year-old. That year, the average OPS in the league was just .672, so Beltre’s mark was over 300 points higher than the norm for the whole league; Harper’s current mark is over 400 points higher than the average hitter in the SAL this year.

Josh Hamilton? He didn’t make his full season debut until age 19, and then he hit .302/.348/.476. B.J. Upton? .302/.394/.445 in 453 plate appearances – Harper already has more home runs than Upton had in the SAL at the same age, though Upton spent almost the entire year at that level. His brother hit just .263/.343/.413 in full-season ball at this age.

Really, to find a similar performance at age 18, you probably have to go back to Ken Griffey Jr in San Bernardino in 1988. In 58 games at the level, he hit .338/.431/.575 when the league average hitter was putting up a .256/.354/.351 line. The numbers aren’t quite as staggering, but the sample size was larger and they came in the California League, which is high-A ball- a step up from where Harper is now. Given adjustments for league context and quality of competition, Junior’s performance is at least on par with what Harper is doing now, and probably a bit better. But that’s the best we can do.

Harper’s performance so far is only slightly less impressive than what Ken Griffey Jr did in 1988 (the only year he spent in the minors) and probably on par with Alex Rodriguez in 1994 (in what probably should have been his only year in the minors). Griffey and Rodriguez are two of the best players in the history of the game, and (PED issues for Rodriguez aside), easily first ballot Hall-Of-Famers. They’re inner-circle guys – the best of the best.

That’s who Harper is keeping up with right now. Instead of going to prom, Harper is putting himself in the conversation for best prospect in recent history. He can’t keep this pace up, but he doesn’t have to – even with some significant regression in his numbers, this is still going to go down as one of the best age-18 seasons we’ve ever seen. Harper is proving that he is worth every bit of the hype he’s ever received.