What's up with this? He's 20 years old with a slew of baseball gifts, but durability isn't one of them.
Not that Harper is alone with these issues. It seems as if most players in the Major Leagues today are just one diving catch, sprint to first or sizzling fastball shy of joining the disabled list.
Ask the Yankees. Nearly all those in pinstripes are susceptible to having "DL" next to their names. I mean, Yankees cleanup hitter Curtis Granderson has been disabled twice with forearm and finger injuries, and the season is barely two months old.
As for pitchers, Tommy John surgeries are an epidemic. Just in the last couple of weeks, Braves star relievers Jonny Venters and Eric O'Flaherty had the surgery, and they were the sixth and seventh Braves pitchers to do so in the past five years.
Remember, too, we're living in a baseball generation of strict pitch counts, starters going every fifth day instead of four, complete games as dinosaurs and advanced fitness training.
Shouldn't the arms of pitchers be stronger? Not only that, with the aforementioned training for everybody, shouldn't players in general have more durability?
It's not happening.
Harper is the epitome of it all. He's an outfielder for the Nationals who plays hard. He plays really hard. He plays so hard that his knees already are threatening to resemble those of Willie McCovey or Andre Dawson at the end of their careers.
Earlier this month, Harper slammed into a wall at Dodger Stadium, where he first damaged his left knee while suffering a gash to his chin that required 11 stitches. He reinjured the knee three times on Sunday in a home game against the Phillies. There was his fouling a pitch off the thing, and there also were his two head-first slides.
Nationals manager Davey Johnson has seen enough. Although he played during the hard-nosed era of the 1960s and '70s, he urged Harper to begin sliding with his feet instead of his head.
Is that really Harper's problem, though? What comes to mind is a discussion I had not long ago with the guy who virtually invented and perfected the head-first slide -- Pete Rose.
And guess what? Rose never was hurt.
"I never worried about my fingers getting broken or anything like that. It never happened to me," Rose told me back then, recalling his 24-year career that included 17 trips to the All-Star Game, a National League Rookie of the Year Award, MVP honors of the league and of the World Series and a spot on the Major League Baseball All-Century Team.
Rose also has more hits than anybody in baseball history, but here's what makes his accomplishments even more impressive: 10. That's how many games he missed during the entire 1970s. During 10 seasons, he played in 160 games or more, and that includes the 162 he played for the 1982 Phillies at 41 years old.
Said Rose to me, "I could always tell when I was in a good streak and getting some extra-base hits, because I always had band-aids and scabs on my elbows and my knees. Not my belly. When you do the head-first slide the right way, that's where you get the strawberries. Nowhere else. It's really not something you can practice."
No, the head-first slide has to be in you. It was part of Rose's competitive spirit, and that spirit dominated his era -- along with the ones before that. Even so, despite such a relentless approach to playing, you still didn't have many guys missing games as you do now.
Or so it seemed.
Ty Cobb was Rose of the early 20th century, but despite his reckless abandon style, he played and played and played. Walter Johnson's arm was so famously dependable that he spent nine straight years throwing more than 300 innings during a season.
Stan Musial. Hank Aaron. Bob Gibson.
They all played and played, too.
Then there was the stretch drive of Rose's era, when Steve Garvey also never left the lineup. The same went for Dale Murphy, who had the same Iron Man reputation as Rose and Garvey while starring on Braves teams that often were as lackluster as Rose's Big Red Machine and Garvey's Dodgers were potent.
The point is, Murphy played anyway.
So did Billy Williams, and he did so long enough with the Cubs that he played in 1,117 consecutive games into the early 1970s. And here's the thing: His streak isn't even in the all-time top five.
You already know Cal Ripken Jr. (2,632) and Lou Gehrig (2,130) are at the top of the list, and they will be forever.
Then again, Prince Fielder is looking old school. He's the slugging first baseman of the Tigers who is more than that. He'll dive in a flash for grounders. He'll finish his mad dashes for second in search of stretching a single into a double with (dare I say) a head-first slide.
Fielder does all of that, but he never gets hurt -- well, not enough to stop playing. He hasn't missed a game since Sept. 14, 2010, when he was with the Brewers. Entering Tuesday's action, his consecutive game playing streak was at 393 and counting.
So Fielder is 2,240 more consecutive games from Ripken.