As the first regular season game to feature Mike Trout and Bryce Harper, Monday night's Angels-Nationals contest was preceded by considerable hype. It's not difficult to understand why. Trout and Harper are generational talents who debuted on the same day in 2012 (though Trout had a cup of coffee in 2011, as well) and went on to win their respective leagues' Rookie of the Year awards. Harper, who was considered one of the best high school hitters of all time, was the top pick in the 2010 draft and, in 2012 at the age of 19, turned in what was arguably the greatest season by a teenaged hitter in the history of the game. Trout, who is 14 months older and wasn't taken until the 25th overall pick in 2009, simultaneously had what might have been the greatest age-20 season by an everyday player in the game's history.
Trout has since emerged as baseball's best player. The debate surrounding the last two American League Most Valuable Player awards has shown that many support that title going to Tigers first baseman Miguel Cabrera. But Trout hits for average and power and gets on base as well as if not better than Cabrera, and is also an elite, high-percentage basestealer and baserunner and an excellent defensive centerfielder. Even many Cabrera supporters will admit that, divorced from team performance and the various interpretations of "valuable," Trout is the best player in the game. Indeed, the deeper Trout gets into his career without regressing from the heights of his age-20 season, the more he looks like one of the best players ever, drawing comparisons to Mickey Mantle in terms of all-around ability and Albert Pujols in terms of his immediate ascension to greatness.
By comparison, Harper's rise to the ranks of the game's elite players has been more gradual. Part of that is due to his relative youth and part of it is due to the various injuries he suffered last year in his age-20 season. From Aug. 29 of his age-19 season in 2012 through the end of April of his age-20 season in 2013, Harper hit .342/.417/.703 with 19 home runs in 248 plate appearances across 60 games. That's a 50-homer pace over a full season, the sort of power expectation that preceded him to the major leagues. However, on May 1 of last year, Harper ran into the rightfield wall at Turner Field, straining his right shoulder. Less than two weeks later, he ran into the rightfield wall at Dodger Stadium, opening a gash on his face. Later that same week, he ran into the rightfield wall at Petco Park and banged up his left knee, resulting in bursitis and a disabled list stint that lasted for all of June and required offseason surgery.
The argument can easily be made, then, that Harper was never healthy after his hot April last year, which would help explain his disappointing .254/.351/.420 line over the season's final five months. Already this season, he has had to deal with tightness in his left quad, an injury which made his rookie manager's decision to pull him from a game on Saturday due to a lack of hustle on a weak chopper back to the pitcher a curious one.
That injury caveat, combined with the fact that Harper is still just 21, has allowed expectations to remain sky-high for the Nationals' leftfielder. Indeed, both Jay Jaffe and myself made Harper our preseason pick for National League MVP this year (while all six of our SI.com experts picked Trout for the AL). For now, however, Harper isn't yet in the top tier of National League regulars.
Using Baseball-Reference's wins above replacement as a blunt but informative instrument, here's a list of the top National League position players in bWAR since the start of the 2012 season:
Looking at that list reveals two tiers. The top seven men -- McCutchen, Molina, Posey, Votto, Wright, Gomez and Goldschmidt -- are legitimately the best everyday players in the National League. Two years ago, Braun may have been the best player in the National League, if not all of baseball, but the combination of his doping suspension and a thumb injury have knocked him out of the top tier. Still, his strong start to this season (.306/.342/.625 and tied for second in the majors with six home runs) despite continuing thumb issues suggests that he still belongs in the conversation, perhaps a tick below that top seven for now. Headley, however, probably doesn't belong on this list. He's there simply because of a career year in 2012 that it is unlikely he'll ever repeat given that he'll turn 30 in May and has hit just .243/.336/.387 since.
That leaves five players who happen to be the youngest on the list. Simmons and Heyward, both Braves, benefit from very favorable fielding evaluations. Both are indeed excellent defensive players, with Simmons among the very best in the game at any position, but it's hard to trust defensive evaluations enough to say that their respective 1.6- and 1.3-win advantages over Harper are meaningful. Stanton and Freeman, the former of whom also dealt with injuries last year and the latter of whom also plays for Atlanta, are effectively tied with Harper.
Looking at things that way, Harper is in the second tier with those other four younger players. Braun and Matt Kemp, two players with elite talent whose careers have been derailed in recent years but who are both active and healthy and working to re-establish themselves among the best players in the league this year, could also be in that group.
Yet, even in that second tier, Harper stands out, not necessarily because of his performance, but because of his age. Harper is three years younger than the other four under-25 studs on that list. It's one thing to say Harper has been roughly as valuable as Stanton, Freeman, Heyward and Simmons over the last two years, but it's another entirely to point out that he has been roughly as valuable in his age-19 and -20 seasons as those four have been in their age-22 and -23 seasons. Harper won't turn 22 until October, so there's good reason continue to believe he has greater potential than any of the other four.
Heyward serves as something of a caution here. The Braves' rightfielder compiled 8.9 bWAR in his first two major league seasons at the ages of 20 and 21, but injuries have arrested his progress. His age-20 season remains his best, with career highs in bWAR (6.4), batting average (.277), on-base percentage (.393), OPS (.849) and OPS+ (131), and he is off to another slow start this season. Harper hasn't yet acquired a reputation for fragility, as the 24-year-old Heyward has, and he is is still expected to stay healthy if he can avoid running full-speed into walls. Heyward, though, illustrates how potential can evaporate, a lesson driven home this February when Freeman, Simmons and closer Craig Kimbrel all received major extensions from Atlanta worth between $42 million (Kimbrel) and $135 million (Freeman) while Heyward settled for $13.3 million over two years.
Heyward's lack of progress also throws Trout's success into greater relief. Heyward arrived in the majors with arguably more hype than Trout, both becoming everyday players at the age of 20. After a hot start in his rookie season, however, Heyward has struggled and been felled by injuries, while Trout rapidly ascended to true greatness*. Here's hoping that, as the current season progresses, starting with two more games between the Nationals and Angels on Tuesday and Wednesday nights, it is Trout, not Heyward, with whom Harper remains most closely associated.
*Say what you want about WAR, the size of Trout's lead and his age relative to the rest of this list is astonishing:
Top bWAR totals, all players, since start of 2012 season: