The National Football League cleared Peyton Manning of involvement in doping on Monday, saying there was "no credible evidence" the legendary quarterback had used or been provided with performance enhancing drugs. An NFL statement said investigators had spent seven months probing allegations aired in a documentary by Al-Jazeera America in December which alleged human growth hormone had been mailed to Manning's household in 2011. The claims were made by Charles Sly, a former pharmacist at the Guyer Institute in Indianapolis, where Manning starred for the NFL's Colts for 14 seasons.
