Major League Baseball already has a $300 million contract. Its first $400 million contract could come soon.

Call it a hunch based on where Manny Machado and Bryce Harper are in their careers.

The Baltimore Orioles’ third baseman and the Washington Nationals’ right fielder have much in common. Both were elite prospects before they hit the ground running in the majors in 2012. Both have been among the best at their respective positions since then. Both are just 24 years old. And both are slated to hit free agency after the 2018 season.

Thus, the occasional buzz about one of them being baseball’s first $400 million man. Bob Nightengale of USA Today was the latest to float that figure over Harper’s head. Ken Rosenthal of Fox Sports (h/t ESPN.com’s Kyle Brasseur) hung the figure over Machado’s head last summer.

The ideal scenario is for both of them to get $400 million, as Nathaniel Grow of FanGraphs highlighted in 2015 how players weren’t getting their fair share of baseball’s revenue pie. Two $400 million contracts would go a longer way toward fixing that than just one.

But we must be practical. It’s likely that only one of them will break the $400 million barrier. Assuming that’s a matter of who’s more deserving, we must pit Machado and Harper against each other in relevant categories.

    

Upside

Upside, eh? Well, only one of the players in this discussion has authored one of baseball’s all-time greatest seasons.

Remember Harper’s 2015 season? Yup, that’s the one.

He led MLB in on-base percentage (.460) and slugging percentage (.649) and co-led the National League with 42 home runs. By OPS+, his offensive performance was the best since Barry Bonds in 2004. Baseball-Reference.com put Harper’s wins above replacement at 9.9—a mark that’s been reached only 61 other times among hitters.

Harper’s defining characteristics in 2015 were his advanced approach and his booming power. The former has roots in the 13.5 walk percentage he posted in the minors. The latter had scouts drooling even before he was the No. 1 pick in the 2010 draft. Baseball America rated Harper’s power as a true 80-grade tool.

As such, Harper’s 2015 was less of a random flare-up and more of an inevitability. That was the player he was supposed to be—and, thus, could be again.

For his part, Machado is no slouch. He was worth 6.7 WAR in 2013 and found that same neighborhood in 2015 (7.1) and 2016 (6.7). The first time he did it, he was an otherworldly defender with a decent bat. He’s enjoyed the best of both worlds since 2015, averaging a 130 OPS+ and 36 homers while playing defense that, while short of otherworldly, is still great. Either way, we’re talking superstar-level stuff.

However, whether Machado can get any better is a good question.

Baseball America figured he would be only a 20-homers-per-year guy, so he’s already way ahead of those early power projections. His power did tick upward after first exploding in 2015, but not to a degree that suggests he has a bunch more in the tank.

The jury’s also out on whether Machado can amplify his hitting talent with increased patience. He took a big step forward in that department in 2015, lowering his swing and chase rates and drawing more walks. But that didn’t last, as his improvements regressed in 2016.

This is not to say Machado’s game can’t evolve. It’s just to say he seems to be what he is: a superstar for sure, but one without Harper’s upside.

Advantage: Harper

    

Consistency

Upside is well and good, but what would a team with a $400 million contract offer in hand rather have: a guy who can be great, or a guy who it can count on being great?

Given the size of the bet being made, probably the latter, right?

So let’s confront the elephant that was stampeding through the room marked “Upside.”

Harper owns the best individual season of these two, but Machado is having the better career. He’s been worth 3.2 more WAR than Harper despite playing in 49 fewer games. He’s also topped six WAR thrice to Harper’s once.

There haven’t been wild fluctuations in Machado’s performance like there have been in Harper’s. If we line up their yearly OPS+ numbers, for example, we see a squiggly line and a relatively straight one:

On the whole, Harper’s career 137 OPS+ trumps Machado’s 117 OPS+. But based on the early portion of his career, how consistently Harper’s going to live up to his career mark is anyone’s guess. There’s nothing in Machado’s track record, meanwhile, that suggests similar peaks and valleys are imminent.

On the other side of the ball, Machado’s defense peaked in 2013, when he put up a 31.2 ultimate zone rating and 35 defensive runs saved. But on either side of that are well-above-average performances. In total, he’s been an elite defender through the lens of either UZR or DRS.

Harper’s defensive performance is tougher to pin down due to how much he’s moved around the outfield. He’s mostly been good, compiling a 17.4 ultimate zone rating and 24 defensive runs saved. But rather than maintaining a baseline of above-average defense like Machado has, Harper has had years when his defense has been rated negatively by UZR or DRS.

Bottom line: Based on their performances to this point, only one of these guys is a safe bet to be a great player in any given year.

Advantage: Machado

    

Durability

And now for the fundamental reason why Harper’s performances have fluctuated so wildly: The dude can’t stay healthy.

We got an inkling of that in 2013 and 2014, when Harper was limited to 218 games due to major injuries to his knee and thumb that were accompanied by a handful of nagging injuries.

The bright side at the time seemed to be that he could avoid further trouble by looking after himself on the field, which he vowed to do ahead of 2015.

“It’s more impact stuff. Hitting the wall, blowing the bursa. Sliding into third base on a triple and tearing my tendon,” he said of his injury troubles that spring, via Chelsea Janes of the Washington Post. “So, this year, I’ll just play a little smarter.”

This paid off, as Harper played in 153 games in 2015. Nonetheless, it turned out his problems weren’t solved for good. Although he played in 147 games in 2016, Tom Verducci of Sports Illustrated reported Harper was plagued by a shoulder issue that hindered him at the plate and in the field.

The black marks on Machado’s record are the knee issues he ran into in 2013 and 2014. A ligament tear in his left knee ended his ’13 season early. A year later, an injury to the same ligament in his right knee ended his ’14 season early. But then he came back and played in all 162 games in 2015 and in 157 games in 2016. In all, he’s played in more games over the last two seasons than just one player.

This is a comparison between one guy who’s not past his injury troubles and one who is. Neither is Cal Ripken Jr., but one is more Cal Ripken-y than the other.

Looking forward, Machado is no more likely to be beat up by third base than Harper is by right field. The list of guys who played regularly at third base after 30 and the list of guys who played regularly in right field after 30 look awfully similar.

Advantage: Machado

    

Survey Says: Machado

There are other factors that could be weighed here. Marketability, for example. Blockbuster movies need lead actors who look good on posters. All other things being equal, baseball teams prefer to operate similarly.

But that may be a moot point in this case because all other things aren’t equal.

Harper has the talent to be worth a $400 million contract. And while he’s only put that talent on full display just once so far, that could obviously change in 2017 or 2018. He has the ability and the time to shift the nature of the conversation.

But if things stay the way they are now, Machado is the safer bet for a $400 million contract. Even if he never gets any better, he’s good enough now and should remain good enough from both a talent and durability perspective.

Again, here’s hoping both land $400 million contracts. But if only one of them can, right now it’s clear who that one should be.

    

Stats courtesy of Baseball-Reference.com and FanGraphs unless otherwise noted/linked.

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