Louis Riddick says people should be more sympathetic toward and less critical of Josh Gordon. (1:20)

The New England Patriots had an elaborate security plan in place to try to prevent the exact slip-up that cost wide receiver Josh Gordon his season and quite possibly his NFL career, sources told ESPN.

The Patriots assigned people to be with Gordon at all times so that he could avoid the temptations that landed him on the suspended list last week, according to sources.

Sources believe that Gordon somehow eluded New England's security team during the Patriots' Nov. 18 bye weekend. Gordon was suspended indefinitely Thursday for violating the terms of his conditional reinstatement under the NFL's drug policy.

Gordon, 27, had been suspended by the NFL for most of the previous four seasons because of multiple drug violations. Based on the discipline schedule in the collective bargaining agreement, Gordon would be facing banishment from the league for any positive test, though he could still apply for reinstatement.

Earlier Thursday, Gordon tweeted that he was stepping away from football to focus on his mental health.

"I take my mental health very seriously at this point to ensure I remain able to perform at the highest level. I have recently felt like I could have a better grasp on things mentally. With that said, I will be stepping away from the football field for a bit to focus on my mental health," Gordon said in his statement.

Gordon went on to thank coach Bill Belichick, team owner Robert Kraft, the Patriots organization and the fans. A short time later, the Patriots said in a statement that they support Gordon "in his continued efforts to focus on his health."

ESPN's Mike Reiss contributed to this report.