The 24-year-old Nationals right fielder looks on his way to his second National League MVP award, hitting .349 with a 194 OPS+ entering Tuesday while putting himself on pace for 49 home runs and 139 RBIs. His Nationals have been similarly effective, jumping out to a 26-17 record. They might be the team to beat in the senior circuit.

Quietly, Mike Trout has been almost as good or slightly better than Harper, depending on one’s view of sabermetrics. Trout’s raw numbers are slightly worse than Harper’s — .343 batting average and three fewer RBIs entering Tuesday — and his Angels have struggled, though Trout bests Harper in OPS+ and WAR. In fact, Trout’s topped Harper for OPS+ and WAR every season except 2015.

MORE: Ranking the 25 worst-ever Hall of Fame selections

It’s funny. When Harper hit the cover of Sports Illustrated at 16, stardom seemed inevitable. Few prep ballplayers have attracted as much hype, from David Clyde to Ken Griffey Jr. to Alex Rodriguez. But Harper’s career has been mixed. Aside from his 2015 MVP season, he’s dealt with injuries and provided solid but unspectacular play. He could be the next Reggie Jackson. Or he could be the next Fred Lynn. It’s still too soon to tell.

Meanwhile, Trout has rarely operated at less than peak form, averaging 9.4 WAR per 650 plate appearances for his career. Baseball-Reference.com rates 8 WAR as an MVP-caliber season. Not surprisingly, Trout has finished first or second in MVP voting every season but 2011. He’ll turn 26 in August and is already better sabermetrically than several Hall of Famers. Barring catastrophe, his enshrinement is only a matter of time.

The same can’t be said for Harper, at least not yet, though he’s starting to look like more of a probable Hall of Famer.

Cooperstown chances: 90 percent for Trout, 50 percent for Harper

Why: A lot about Trout’s and Harper’s Hall of Fame chances hinge on their health. Trout has been a tank, averaging 158 games a season from 2013 through last year. Harper’s struggled more to stay healthy, averaging 131 games over his first five seasons in the majors.

Healthy, Harper’s been an All Star-level player, earning nods for the National League team all but one season. These haven’t been courtesy nods either. Harper’s averaged 5.7 WAR for every 650 plate appearances for his career, with Baseball-Reference.com rating 5 WAR as an All-Star season. Granted, Harper’s only reached 650 plate appearances one season, his 2015 MVP campaign. Entering this year, he’s averaged 554 plate appearances.

Harper might be turning the page this season health-wise, having played in 40 of the Nationals’ 43 games so far. With his style of play, though, or his bulky frame, Harper might have a propensity for injury. This doesn’t bode well for his Hall of Fame chances.

MORE: The most likely Hall of Famer on every team entering 2017

So what might injuries cost Harper if they persist? Perhaps seven home runs a season, with Harper averaging 24 home runs his first five seasons but 31 homers per 162 games. This might sound inconsequential and like something that will even out over time. Seven homers a year for 20 years, however, is 140 homers. It’s the difference between more than 600 home runs and barely 450.

Six-hundred home runs will pretty much guarantee a player enshrinement, at least at some point with Barry Bonds starting to look like a probable Cooperstown selection from the Baseball Writers’ Association of America. Sammy Sosa, the only other eligible player with 600 home runs not in the Hall of Fame, has struggled to draw more than a small percentage of votes so far. But he could also be a committee pick at some point.

Meanwhile, numerous players have 450 or so home runs and are not enshrined, the Adam Dunns, Dave Kingmans and Carlos Delgados of the baseball world.

With continuing injuries but a relatively long career, say 15 to 20 seasons — which seems perfectly reasonable with Harper debuting as young as he did — Harper might wind up in roughly the same territory as Dunn, Kingman or Delgado. This will doom his Hall of Fame chances. Dunn last played in 2014 and isn’t yet eligible with the BBWAA, but Kingman and Delgado each lasted just one year on the ballot.

The best that can be said for candidates such as Dunn, Kingman and Delgado (particularly Delgado, among the most underrated players in baseball history) is they have their supporters. But then, many fringe Hall of Fame candidates have supporters on the internet. There are 50 or 100 retired players, maybe more, who can garner blog posts and occasional news columns, though they don’t have much hope of getting in. Such is the Hall of Fame, which keeps out so many more good players than it lets in.

MORE: The 10 best MLB players, for talent, without serious Hall of Fame cases

Or there’s the option for Harper to shine more brightly and end his career more spectacularly. Kevin Mitchell comes to mind, the bombastic star who won an MVP at 27 but played just 264 games in the majors after his 30th birthday. For peak value Hall of Fame candidates, Mitchell ranks among the best offensive ones in baseball history, though seemingly few people are making his case.

Similar things can be said about Fred Lynn, who had a .308 batting average through his age-28 season, but averaged 114 games thereafter. “Every year where I (got) to 140 games, I had really good years,” Lynn recently told Sporting News. “I just needed to play more games. That’s all. I’ve never in my life done poorly if I played a lot, just never have.”

Harper’s logged just 140 games in a season just twice so far, though he was an MVP one of those years.