In an op-ed for Sunday’s edition of the Chicago Sun-Times, Bears receiver Brandon Marshall discussed Junior Seau’s passing and the difficulty that NFL players have with depression.

“Looking at the situation with Seau and other cases with retired athletes, I think our focus should be more on why the transition seems to be so hard after football. As athletes, we go through life getting praised and worshipped and making a lot of money. Our worlds and everything in them — spouses, kids, family, religion and friends — revolve around us. We create a world where our sport is our life and makes us who we are. When the game is taken away from us or when we stop playing, the shock of not hearing the praise or receiving the big bucks often turns out to be devastating. The blueprint I am creating for myself will help not only other athletes, it will help suffering people all over.”

Marshall makes an excellent point. What happens when fans stop cheering their name? What happens when they’re not adored and admired? What happens when they stop getting everything handed to them in life?

That last question isn’t meant to be crass – it’s reality. Because of their gifted athletic abilities, players are privileged from a very young age. They’re used to people making them feel special and handing them opportunities. All of a sudden when that’s gone, what happens? Talk about a transition.

Marshall’s right – what happens when the lights finally go down? Many athletes only know one life and once that’s over, they often don’t know what to do. I talk to former athletes and a lot of them same thing: It’s jarring when their playing careers are over. Some know how to handle it, others don’t.

We can assume that Seau had mental troubles stemming from using his head as a battering ram for 20 seasons in the NFL. And if he had the same condition as Dave Duerson, then we’ll find out soon enough.

But maybe Marshall is right and concussions aren’t the only problem – they’re just part of a bigger, more frightening picture.

The North County Times reported on Wednesday that former Chargers, Dolphins and Patriots linebacker Junior Seau passed away after a self-inflicted gunshot to the chest. Seau was 43 years old.

There have been conflicting reports about who found Seau’s body at his Oceanside, California home. Some media outlets have stated that it was his housekeeper that discovered his body, while others have reported that it was Seau’s girlfriend who eventually found him and called authorities. A handgun was found nearby and police have confirmed that Seau committed suicide.

Seau was drafted fifth overall in 1990 by the San Diego Chargers, whom he played with for 12 years before he was traded to the Miami Dolphins in April of 2003. He later signed with the New England Patriots for three years before leaving the game following the 2009 season.

During his 20 years in the NFL, Seau racked up 1,849 tackles, 56.5 sacks and 18 interceptions. He went to 12 Pro Bowls during his career and was named All-Pro 10 times. He was a part of two AFC Championship teams (1994 Chargers and 2007 Patriots) and was named AFC Player of the Year in 1994. He’s a member of the San Diego Chargers Hall of Fame and was named NEA NFL Defensive Player of the Year in 1992.

Just over one year ago, former Chicago Bears safety Dave Duerson committed suicide in the same fashion as Seau. Three months later researcher neurologists at Boston University confirmed that Duerson suffered from a neurodegenerative disease linked to concussions.

Renowned for his hard hits and raw energy, Seau was easily one of the best outside linebackers to have ever played the game.

Dave Duerson, a key member of the Super Bowl-winning 1985 Bears team, committed suicide on Thursday by shooting himself in the chest. As NFL Fanhouse wrote, it was a sad end to a life of a man who was troubled after leaving football.

But while this story has a tragic ending, Duerson managed to leave a generous gift before leaving this world.

In a suicide note he sent to friends, Duerson asked that his brain be donated to the Center for the Study of Traumatic Encephalopathy at Boston University School of Medicine. The Center has been leading the way in research into how brain damage — including injuries suffered in collisions on the football field — can lead to health problems later in life. One theory is that people who have a history of repetitive brain trauma are more likely to experience depression, and studying Duerson’s brain may help researchers determine whether brain damage suffered on the football field led to the depression that ultimately caused him to take his life.

Chris Nowinski, a former Harvard football player turned professional wrestler turned co-director of Center for the Study of Traumatic Encephalopathy, said Duerson had indicated he wanted to be studied in the hopes that some day, we’ll know more about how to protect football players from suffering brain damage on the field.

These are the stories that many fans acknowledge but quickly forget because we don’t want anything bad to be associated with a game that is so cherished. But Duerson’s story is just one of many involving former football players that have been affected by a sickness after their playing days are over. Whether it’s depression, addiction to painkillers or serious brain trauma, there are many, many examples of former players that are dealing with serious health problems.

Football is a nasty sport. It always has been and probably always will be. The game has come a long way since leather helmets and no shoulder pads, but more research must be done. These players are human beings first and foremost and it’s difficult to hear stories like Duerson’s. Hopefully his final gift can provide researchers insight about what can be done to protect current and future players.