Free-agent wide receiver Josh Gordon applied for reinstatement to the NFL on Wednesday, a source confirmed to ESPN.

Gordon was suspended indefinitely by the NFL on Dec. 16 for violations of the league's policies on performance-enhancing substances and substances of abuse. It was his sixth suspension since the 2013 season and the fifth for some form of substance abuse, according to ESPN Stats & Information.

Gordon's attorney, Adam Kenner, confirmed to ESPN that Gordon had a setback after the death of his brother last fall. Gordon tweeted about losing his older brother on Nov. 11, the day he made his Seahawks debut.

"Josh had a lapse because of his brother's death. That set him back. But since that time, he has realized how important it is for him to take the right steps, do what's proper, and understand how to manage these issues. He's installed the right team around him to make sure he's on the right path. He understands he's been given every chance. He looks forward to making the most of this," Kenner said in a separate statement to NFL Network.

Gordon applied for reinstatement through the NFL Players Association, which will submit the application to the NFL. Commissioner Roger Goodell will oversee Gordon's reinstatement attempt and will make the final decision as to if and when his indefinite suspension is lifted as well as how many more games, if any, Gordon will be suspended.

Gordon's hope is to have his indefinite suspension lifted in time to participate in training camp. In theory, he could take part if his indefinite suspension is lifted before then, even if Goodell were to suspend him for a set number of games to begin the 2020 season.

Gordon was conditionally reinstated in mid-August of last year after applying for reinstatement in July. However, it's not clear how the coronavirus pandemic may impact the timetable this time.

If reinstated, Gordon would become an unrestricted free agent for the first time in his career. He played 2019 on a one-year deal as a restricted free agent.

The Seattle Seahawks claimed the one-time Pro Bowler in November after he was released off injured reserve by the New England Patriots. Gordon, 29, had seven catches for 139 yards as the No. 3 wide receiver with Seattle, including a 58-yard reception during a 30-24 victory over the Carolina Panthers the day before he was suspended.

Gordon missed the 2015 and 2016 seasons as a member of the Cleveland Browns and was suspended in December 2018 for violating terms of his reinstatement, missing the final three games of the season with the Patriots.

He was suspended for the first two games of the 2013 season but still caught 87 passes for nine touchdowns and a league-leading 1,646 yards and was named to the All-Pro team.

Gordon has played just 63 games since the Browns selected him in the 2012 supplemental draft. Overall, he has caught 247 passes for 4,252 yards -- an average of 17.2 yards per catch -- and 20 touchdowns.

NFL Network first reported that Gordon had applied for reinstatement.

Gordon considered the Seahawks an ideal landing spot last year in large part because of his affinity for quarterback Russell Wilson. Gordon has remained in the Seattle area since his suspension and has been posting pictures of his training sessions on social media.

The Seahawks have Phillip Dorsett and David Moore competing to be their No. 3 wide receiver behind Tyler Lockett and DK Metcalf.

ESPN's Field Yates contributed to this report.