VIDEO: 'One of the toughest things I've ever had to do': 49ers' Joe Montana remembers Dwight Clark at memorial in San Francisco

SAN FRANCISCO (KGO) -- Former San Francisco 49ers great Joe Montana spoke about his friend Dwight Clark at a memorial service at San Francisco's Grace Cathedral on Wednesday.

Montana shared that Clark had asked him to speak at his funeral before he died.

"I had a few choice words for him, which I can't say in church," Montana said.

He also noted, "I'm not one for usually writing things down, but I won't lie, this is probably one of the toughest things I've ever had to do."

Other family and 49ers legends spoke at Clark's memorial service. Click here for a look.

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