Legendary San Francisco 49ers wide receiver Dwight Clark announced in a blog post Sunday that he has ALS.

The central figure in “The Catch” – the famous touchdown reception he made in the waning moments of the 1981 NFC Championship game against the Dallas Cowboys – Clark wrote that he “started feeling weakness” in his left hand in 2015. Months later, he was diagnosed with amyotrophic lateral sclerosis, also known as Lou Gehrig’s disease.

“While I’m still trying to wrap my head around the challenge I will face with this disease over the coming years, the only thing I know is that I’m going to fight like hell and live every day to the fullest,” he said.

Clark, 60, did say the disease appears to be progressing slower than in other patients.

He played all nine years of his NFL career with the 49ers, and said he suspects football played a role in the diagnosis.

“I encourage the NFLPA and the NFL to continue working together in their efforts to make the game of football safer, especially as it relates to head trauma,” Clark implored.

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