A pro-marijuana billboard is seen near the Denver Broncos stadium in Denver September 5, 2013. Football fans heading to the NFL season opener between the Super Bowl champion Baltimore Ravens and the ... more 
A pro-marijuana billboard is seen near the Denver Broncos stadium in Denver September 5, 2013. Football fans heading to the NFL season opener between the Super Bowl champion Baltimore Ravens and the Denver Broncos on Thursday will be greeted by the billboard urging the league to loosen its policy on marijuana use by players. The billboard refers to Colorado's legalization of recreational marijuana. REUTERS/Rick Wilking (UNITED STATES - Tags: SPORT FOOTBALL SOCIETY DRUGS) less 
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Reuters | Photo By RICK WILKING / REUTERS
Thu, Sep 5, 2013 7:20 PM EDT