We shouldn't require reminders. We should know, innately, that death plays no favorites, that not even the strongest escape this planet alive.

Somehow, though, death always jars us when it intersects with sports, making this one of the saddest and most jarring weekends in memory.

Friday morning, we learned that Twins legend Harmon Killebrew will end his battle with esophageal cancer and spend his remaining days in hospice care.

Friday night, we learned that former Wild enforcer Derek Boogaard had been found dead at his Minneapolis apartment.

The men shared few connections. Killebrew is 74 and those close to him, such as Jack Morris, expected this news. Even those far removed from Killebrew's inner circle realized that this form of cancer was particularly devastating, especially for a man of Killebrew's age.

Boogaard was 28 and those close to him worried about his recovery from a concussion. At 6-7 and 258 pounds, possessing the toughness of a man who made his living with jaw and fists, he would have seemed, to an outsider, invulnerable as Killebrew in his prime.

They are not invulnerable, though. Beneath the muscle and machismo of a pro athlete beat all-too-mortal hearts.

We shouldn't require these reminders, especially we Minnesotans. We followed Kirby Puckett's descent.

In 1991, he became a part of World Series history. In 1996, he awoke blind in one eye, and retired months later. In 2006, he died after suffering a stroke.

A.E. Housman wrote the most celebrated elegy about interrupted athletic lives: "To An Athlete Dying Young."

The greatest poem ever written on the subject, though, was uttered, extemporaneously, by a product of the Robert Taylor Homes in Chicago, when he announced his retirement in a cramped room deep inside the Metrodome on July 12, 1996.

"Can you all just do me one favor?" Puckett said. "Don't take life for granted, because tomorrow isn't promised to any one of us."

A version of that quote now hangs in the Twins clubhouse, close to Justin Morneau's locker. Saturday night, Morneau, the rare person who befriended both Killebrew and Boogaard, stood under that quote and spoke quietly about a weekend of loss.

"Yesterday was a rough day," he said, speaking of Friday. "Obviously it was rougher for their families, but it was tough. I found out after the game about Boogey, and I was in shock.

"On the ice, he was completely different than he was off the ice. You can ask anybody who knew him. He cared about people. If you asked him what he did and he told you he was a fighter in hockey, you wouldn't believe him."

Boogaard, like Morneau, struggled to overcome concussion symptoms. "With his concussion, he's been checking up on me and seeing how I'm feeling," Morneau said. "He texted me last week to see how I was doing, make sure everything was OK.

"We talked back and forth. He's come down and taken batting practice with us. To get news like this about him, it's not fun."

Many Twins knew that Killebrew was nearing the end of his battle with cancer. Boogaard's death arrived without warning.

"It's almost like, as athletes, you have that feeling of invincibility," Morneau said. "You're out here and you're supposed to be in the best shape of everybody, and that's not supposed to happen. That's why it tends to be more of a shock.

"You're looking at guys in their 20s and 30s who are supposed to be at the peak of health. Something like this happens, and you realize that you're not invincible, and that every day you get to come out here you're lucky, and you should enjoy it."

A visitor pointed to Puckett's quote. "That's it," Morneau said. "That's why what we're going through as a team, even though it's not fun and we're not used to it around here, we can't feel sorry for ourselves just because we're losing baseball games. You look at the big picture, and while obviously everyone wants to have success, you can't feel sorry for yourself because you went 0-for-4. There are people going through a lot harder things."

Fans brought flowers to Killebrew's statue by Target Field, and honored Boogaard by placing flowers outside of Xcel Energy Center.

"Boogey was 28 years old," Morneau said. "That's not supposed to happen to a guy that young."

Jim Souhan can be heard Sundays from 10 a.m. to noon and weekdays at 2:40 p.m. on 1500ESPN. His Twitter name is Souhanstrib. • jsouhan@startribune.com