The Jacksonville Jaguars wide receiver has been suspended indefinitely for breaking the league's substance-abuse policy, and will not be able to apply to be reinstated before the end of the current campaign.
The general manager told reporters: "We've made great strides with Justin here in the last four or five months. We thought we were making good strides and we've had a setback here. It's a complicated matter.
"I think Justin wanted to do the right thing and I think he tried really hard to do the right thing and sometimes people just need to take a break and need more help than what we can provide him, and this break from football is probably going to be a really good thing for Justin and his well-being, which is always our number one priority.
"We're just not going to cut ties with him today. Justin needs support right now. This has never really been about Justin Blackmon the player. It's been about Justin Blackmon the person. It's not in our nature to just turn our back on one of our members that needs our help."
Blackmon missed the start of this season because of another suspension, but managed 415 receiving yards and a touchdown in the four games that he was able to play in.