Gary Plummer played linebacker professionally for 15 seasons, teaming with Junior Seau during the heart of his career with the San Diego Chargers.

The death of Seau has shaken Plummer, who saw his friend just last month at a charity golf tournament. There have been no reports of Seau dealing with concussions in his NFL career but Plummer wondered aloud how many the future Hall of Famer suffered. Seau committed suicide on Wednesday.

Plummer told Cam Inman of the San Jose Mercury News that he estimates he suffered 1,000 concussions during his playing career, which began in the USFL with the Oakland Invaders.

“In the 1990s, I did a concussion seminar. They said a Grade 3 concussion meant you were knocked out, and a Grade 1 meant you were seeing stars after a hit, which made me burst out in laughter,” Plummer told Inman. “As a middle linebacker in the NFL, if you don't have five of these (Grade 1 effects) each game, you were inactive the next game.

“Junior played for 20 years. That's five concussions a game, easily. How many in his career then? That's over 1,500 concussions. I know that's startling, but I know it's true. I had over 1,000 in my 15 years. I felt the effects of it. I felt depression going on throughout my divorce. Junior went through it with his divorce.”

Wow.

Plummer said he asked Seau how he was doing when he saw him last. Seau indicated everything was good. Then, Plummer pulled him aside and asked him how he really was doing. He said he was good. Clearly, Seau was leading a troubled life and there will be plenty of speculation that head trauma could have led to his death.

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Brad Biggs covers the Bears for the Chicago Tribune