Source: MLB to investigate Ryan Howard, Ryan Zimmerman HGH allegations
Ryan Howard, Ryan Zimmerman file defamation suits against Al Jazeera America
Inside Peyton Manning's secret investigation into Al Jazeera documentary - The Washington Post
Angry Peyton Manning denies ever using HGH, calls Al Jazeera report 'completely fabricated' – New York Daily News
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Manning denies report accusing him of human growth hormone use
Taylor Teagarden's PED use is a bad look for Chicago Cubs
Explosive Documentary Links Peyton Manning, Major Athletes To Doping Ring
Report: Peyton Manning sent investigators to look into person behind HGH allegations
MLB Clears Ryan Howard in Drug Probe
The dark side: The secret world of sports doping, Athletics
The dark side: The secret world of sports doping, Athletics
The Secret World of Sports Doping
Angry Peyton Manning denies ever using HGH, calls Al Jazeera report 'completely fabricated' – New York Daily News
James Harrison accused of using undetectable human growth hormone