"I wouldn't have any idea where to get a Molly or what a Molly is," Welker said in an email to The Denver Post. "That's a joke. I don't do marijuana, I don't do drugs. I don't do any drugs."
Welker tested positive for amphetamines from a sample taken shortly after he attended the Derby, sources told ESPN NFL Insider Adam Schefter.
Pro Football Talk, citing a league source, reported that the two-time All-Pro took Molly that was laced with amphetamines. A source told the Post, meanwhile, that the positive test was for Adderall, which can be taken by NFL players but must be cleared by the league -- and Welker didn't have clearance to take it.
Welker, in the email to the Post, argued that the sample was tainted but said he does wonder whether someone put something in his drink at the Derby.
"I'm as shocked as everyone at today's news," Welker told the newspaper. "I want to make one thing abundantly clear: I would never knowingly take a substance to gain a competitive advantage in any way. Anyone who has ever played a down with me, lifted a weight with me, even eaten a meal with me, knows that I focus purely on what I put in my body and on the hard work I put in year round to perform at the highest levels year-in and year-out."
The 33-year-old veteran, who is entering his 11th season, also said he now knows the drug-policy procedures in the league are "clearly flawed," according to his email to the Post, and that he will do everything in his power to ensure they are corrected.
Welker appealed the decision and was excused from practice Aug. 20-21 to attend his hearing, sources told ESPN Senior NFL Analyst Chris Mortensen.
The Broncos open the season Sunday night against the Indianapolis Colts. Welker will be eligible to return to the active roster Oct. 6.
According to ESPN and multiple reports, the reigning AFC champion Broncos were "irate" at the timing of the NFL's decision because it came Tuesday night, after they were done game-planning for the Colts. Typically, the league announces its suspensions earlier than that.
Sources told Schefter that the Broncos, who were aware of Welker's positive test, still thought he would be available to play in the opener -- pending his health -- until the ruling came out.
Welker returned to the practice field Monday as he continues through the NFL's concussion protocol. He would have to be symptom-free to take part in a full practice and then remain symptom-free after that and be cleared to play medically by an independent doctor. Welker suffered his third concussion since Nov. 17 during the Broncos' Aug. 23 preseason game against the Texans.
His suspension is a huge blow to the Broncos' receiving game. Only four wide receivers caught passes for Denver last season, and nearly 60 percent of those receptions will not be on the field for the Broncos in Week 1, as Eric Decker is now with the Jets and Welker is suspended.
"Tonight's news regarding Wes is very disappointing for our team, but we understand the league's authority in this area," Broncos coach John Fox said in a statement released Tuesday. "While it's unfortunate to not have him to start the year, I have full confidence in our wide receivers and expect that group to continue playing at a high level.
"I have no doubt that Wes will remain focused on his preparations for the season and stay in excellent shape during his time away from the team."
Former New England Patriots teammate Tom Brady addressed the receiver's suspension Wednesday.
"That's Wes's situation ... as a friend you hope the best, but this isn't friend time, it's opponent time," the quarterback said.
Brady also was at the Kentucky Derby in May. Asked if he saw Welker taking anything there, he laughed really hard and said, "No comment on that."
Information from ESPN.com Broncos reporter Jeff Legwold and ESPN Stats & Information was used in this report.
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