New York, NY (Sports Network) - Former NFL star linebacker Junior Seau reportedly suffered from a brain disease, likely caused by two decades worth of blows to the head, when he killed himself last May.

Seau ended his life at his home in California with a gunshot to the chest. Many believed he shot himself in the chest to preserve his brain for testing, and his family members donated it to neuroscientists at the National Institutes for Health.

According to a report from ABC News and ESPN, researchers have concluded that Seau suffered from chronic traumatic encephalopathy (CTE), a degenerative disease typically caused by multiple hits to the head.

Seau, who was just 43 years old when he died, was known as one of the hardest hitters during his 20 NFL seasons. He spent 13 years with San Diego, three with Miami and four with New England before retiring after the 2009 season.

The 12-time Pro Bowl selection is just the latest former NFL player to be diagnosed with CTE, which can only be ascertained after death.

Former NFL defensive back Dave Duerson, who played with the Chicago Bears, New York Giants and Arizona Cardinals, also killed himself in 2011 and was found to have CTE. He asked his family to donate his brain for testing.

The Seau report could also be another blow to the NFL in its ongoing issues with concussions and brain disease. Numerous lawsuits have been filed against the league by former players who have alleged the NFL knew about the dangers of concussions and other head injuries, but did nothing to protect the players.

NFL commissioner Roger Goodell has made player safety among his chief concerns in recent years.

The Sports Network