Gates, Richardson and McClain given four-game bans
Four NFL players have received suspensions for substance abuse violations, with three banned for the opening four games of the season.
Antonio Gates, Sheldon Richardson and Rolando McClain have all been handed four-game bans for violating the NFL's substance abuse policy.
San Diego Chargers tight end Gates is an eight-time Pro Bowler and three time first-team All-Pro, racking up over 10,000 receiving yards and 99 touchdowns in a storied career.
But he will be unavailable for the Chargers until after San Diego's Week 4 clash with the Cleveland Browns, putting him in line for a return against the Pittsburgh Steelers on October 12.
Gates, who blamed an ignorance of the risks of "holistic medicines", said: "I have taken extreme care of my body with a holistic approach and I have never knowingly ingested a substance that was banned by the NFL.
"As an NFL veteran and team leader, I should have done my due diligence to ensure that what I was taking for recovery was within the NFL guidelines.
"I'd like to express my sincere apologies to the Chargers, my team-mates, coaches, fans and the league who have always supported me and expected and gotten nothing but the highest level of integrity from me."
New York Jets defensive tackle Richardson reached the Pro Bowl in just his second year in the league last season after earning defensive rookie of the year honours in 2013.
However, with the Jets having a bye week after their Week 4 meeting with the Miami Dolphins in London, he will not see the field until the October 18 game versus the Washington Redskins.
Richardson said: "I don't want this to take away from what the team is trying to accomplish. While I won't be there at the start of the regular season, I will do whatever I can to support my team-mates until I'm able to return to the field."
Dallas Cowboys linebacker McClain retired in April last year only to then reverse his decision and enjoy a stellar campaign with Dallas after being traded by the Baltimore Ravens.
McClain, who reportedly failed a drug test back in February, is joined on the suspended list by Datone Jones, the Green Bay Packers defensive end receiving a one-game suspension for violating the policy.
All four players will be allowed participate in off-season activities and pre-season games.