There's nothing routine about head injuries

The scary thing is that it wasn't at all scary. Justin Morneau(notes) didn't run into a wall. He didn't clash heads with a teammate. He didn't slide face first into a knee. He didn't plow through a catcher. He dove for a ball down the first-base line Aug. 28, his landing seemingly ginger. It wasn't. His brain rattled off his skull. It was happening again.

Morneau isn't with the Minnesota Twins now. The team isn't saying so publicly, but it doesn't expect him back this season, the second consecutive cut short by a concussion. There's no sense in rushing him even if he says he's feeling good, though by now, Morneau knows better. To the chronically concussed, good is a shooting star, gone as fast as it appeared.

And it's why a pall lingers over the Twins' clubhouse these days, one that extends beyond the effects of a 59-89 season, 33 losses in their last 42 games and a negative-168 run differential that's even worse than the Houston Astros' number. Morneau is out, his first-base slot filled by the likes of Luke Hughes(notes) and Chris Parmelee(notes). Denard Span(notes), their center fielder, was hitting .300 on June 3 when he suffered a concussion. He missed two months, went 2 for 35 in his return and hasn't played since Aug. 13, when migraines recurred.

The Twins, more than any team in baseball, now understand concussions are no bogeymen. They can turn the brain into an enemy, a nerve center for pain, fear, depression, all suicidal trigger points. Those are the worst cases. Others suffer from splitting headaches, world-tipping dizziness, extreme vertigo, light sensitivity and the helplessness that accompanies each. The lucky escape unscathed and hope against repeat concussions, which, much like recidivism, prompt far worse punishment the second and third and fourth times.

Growing up in Canada, Morneau played hockey, a sport rife with concussions. Its biggest star, Sidney Crosby, missed half of last season with what was initially deemed a "minor concussion" and still isn't ready to play three weeks before the regular season begins. Boston center Marc Savard could retire at 33 because of an elbow to the head last year from goon nonpareil Matt Cooke. While there's far from definitive proof before medical examinations, the link between concussion-related depression and the deaths of three NHL players this offseason strengthened after each incident, two of which were ruled suicides.

Between the NHL suicides as well as those from concussed former NFL players, the specter of long-term brain damage is the athletic world's new scared-straight program. No longer do leagues allow players to trifle with concussions, not when knowledge remains so limited. If an athlete jams a finger, he misses a week. Pull an oblique and it's month. Blow an elbow and it's a year. Suffer a concussion and it's … well, no doctor can answer that because concussion science is a relatively new field, and it may be one with such disparate answers that they'll never come to a concrete conclusion.

This leaves Morneau, as well as the Twins, in a purgatory of confusion where there is no clock, just hope.

"I don't know how he's feeling," Twins manager Ron Gardenhire said. "Whether he's even going to get back the rest of this year, I don't know. I don't have any answers."

He's not the only one. The latest play looked so innocuous. Alex Avila(notes) hit a ball over the first-base bag. Morneau lunged and missed. It was nothing. Routine effort. Certainly not getting hit in the head by a pitch like Gardenhire did nearly 30 years ago.

He remembers only what he's been told and read. It was Sept. 7, 1983. He was playing for the New York Mets' Triple-A club, the Tidewater Tides, in a playoff game in Columbus, Ohio. The Tides were winning handily when Gil Flores, the team's oldest player, stole second base in the sixth inning. Columbus didn't take kindly to that, and Jesus Hernaiz nailed Gardenhire with the next pitch. Gardenhire crumbled to the ground and awoke to a brawl going on around him. When the fight subsided, his manager, Davey Johnson, asked him to finish the game at shortstop.

"So I played," Gardenhire said. "And I don't remember that game. I don't remember hardly anything about it. I remember hitting an inside-the-park home run after it, and I remember the third-base coach telling me, 'I was stopping you the whole way.' I didn't see."

Gardenhire didn't miss a game that postseason. Tidewater won the Triple-A World Series that season. Turns out Gardenhire, 53, is one of the lucky ones.

Morneau isn't. Span may not be, either. As hard as MLB is trying – establishing a seven-day disabled list for concussions, implementing protocols for the league to clear players before they can return after a concussion, emphasizing education for athletic trainers – this is a game, and people will get hurt, and for a 30-year-old former MVP to need to entertain the idea that his head never will get better is cruel.

"You see how tough it can be for your life," Twins pitcher Kevin Slowey(notes) said. "He's done an awesome job battling it and putting on a brave, strong face. I worry for him as a friend. He's a husband and a father. When you get a concussion like that, it affects your everyday life."

Justin Morneau is supposed to be with the Twins right now, finishing strong, trying to pull his numbers up so he doesn't finish among the league's dozen worst hitters, where he's currently stationed. He's supposed to be worrying more about his baby daughter than whether he can even play his livelihood, and if he can, whether it's strictly as a designed hitter, and if it's as a DH, whether he can stomach the between-innings inactivity.

Beyond that, of course, is the health of the organ processing all of these thoughts. Doctors don't know why Morneau's brain seems to be so sensitive, what happened on that benign dive, how they can fix it. Frankly, they don't know much.

And that's the scariest thing of all.

Other popular stories on Yahoo! Sports:
MLB player's dirty-underwear superstition
Former NFL star's interesting post-football life
NFL's invasive new security plan for fans