Josh Gordon will miss the start of Cleveland Browns training camp to focus on his "overall health and treatment," the wide receiver said in a statement released on Monday.
Gordon was reinstated to the NFL last season having seen his career heavily affected by substance abuse issues.
But, with the Browns set to open camp on Thursday, Gordon posted on Twitter: "I will not be in Cleveland for the start of training camp. Rest assured this too is a part of my overall health and treatment plan.
"I appreciate the awesome support I have received from team-mates, friends, fans, and the Browns organisation. Just like you, I am excited to start the season and I have every intention of being ready and available to join my team-mates soon to help bring winning football to our fans.
Thanks again.. See ya soon..— Flash Gordon (@JOSH_GORDONXII) July 23, 2018
"With the help of the NFL, NFLPA, and the Browns organisation, I have been able to utilise the resources available to me that will ensure my well-being on and off the field.
"By continuing to follow the plan set up by our medical director and his team and taking this time before this season starts, we believe it will help me maintain the progress I've made for not only today but for many years to come. Thank you all for your patience, love, and support! Go Browns!"
Browns general manager John Dorsey added in a statement: "We will continue to support Josh as he receives the care needed to maintain his progress. We are going to respect his privacy while he is away from the team. Josh will be placed on the non-football illness reserve list until he is ready to return."
NFL spokesman Brian McCarthy told Cleveland.com there is "no timetable" for Gordon's return but the team will "address the matter at the appropriate time."
Gordon had served an an indefinite suspension since 2014 for repeated violations of the NFL's substance abuse policy but was activated for the final five games of last season, catching 18 passes for 335 yards and a touchdown in that time.
The 27-year-old, a first-team All-Pro selection in 2013, signed an exclusive rights tender with the Browns in April.
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