The Denver Broncos suffered a loss even before the NFL season officially opens this weekend. Receiver Wes Welker has been suspended four games after testing positive for amphetamine, which violates the NFL's performance-enhancing drug policy, the team said on Tuesday.

In an e-mail to The Denver Post, Welker said, "I'm as shocked as everyone at today's news. I want to make one thing abundantly clear: I would NEVER knowingly take a substance to gain a competitive advantage in any way... have never been concerned with the leagues performance enhancing or drug abuse policies because under no scenario would they ever apply to me, but I now know, that [drug-policy procedures] are clearly flawed, and I will do everything in my power to ensure they are corrected, so other individuals and teams aren't negatively affected so rashly like this."

Welker tried to appeal the penalty two weeks ago, before it was made public, but the league shut him down.

Since the Broncos have a bye in week four of the season, he won't be eligible to return until game six when they face the Jets in New York.