49ers' Colin Kaepernick lashes out at critic on Twitter

by Michael Amato
Bob Stanton-USA TODAY Sports / Reuters

San Francisco 49ers quarterback Colin Kaepernick has been working hard in the offseason, but apparently not hard enough for one of his Twitter followers. 

Kaepernick didn't stop there. 

Serenity now, Colin. Serenity now. 

Although he did receive a tongue lashing, @battman_returns is now up to more than 800 followers.

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