Best, who is eligible to come off the Physically Unable to Perform list as early as next Monday, told reporters Thursday that he took all the tests required for him to be cleared for contact by an independent neurologist on Monday and that he should know the results at some point this Friday.
"I'm just hopeful for the best for tomorrow," Best said. "It took hours. It felt like I was taking the SAT."
Best hasn't played since a Week 6 loss to the 49ers last season after suffering his second concussion of the season. He also suffered one in the preseason against the Browns last year.
If Best does get his long-sought-after clearance, he'd be able to play as early as the team's Monday night game Oct. 22 at Chicago.
The biggest question most people have had regarding Best is why it's taken so long when other players have gone through the concussion protocol and passed. Best said each case was unique, but declined to go into the specifics with his particular case and why it's taken so long to get clearance for contact.
With the new scrutiny across the NFL regarding concussions, Best knows there are many eyes on his case, though.
I guess I'm kind of the poster boy for it," he said. "I think its just timing. The situation I'm in now with the way the concussions are being taken right now is taking a long time and it's a long process right now. I have to take it how it is. Tomorrow, I find out what's the next step."
Best did say that nothing happened during Monday's tests that would indicate to him that he wasn't able to pass them.
The Lions could certainly use him on the field after a 1-3 start. His speed out of the backfield could be the best mismatch advantage Lions offensive coordinator Scott Linehan can exploit outside of receiver
"You all have seen Jahvid when he's played and he's as explosive a player as I've been around," Linehan said. "We're excited about the prospect of him possibly coming back but we're also tempering that enthusiasm knowing that a lot of things have got to be done before that happens.
"I'm just excited for him that he's getting a chance to at least make his impact back on our team when he possibly does come back. But we'll see, it's just great having him in the building and around and knowing that he's doing the best he can to get back on the field."
Best says he's ready to contribute.
"I think I can help them a lot but we'll see when I get back out there," he said. "I know I can go out there and make a difference but whether or not that difference translates into whatever it translates into, we'll see."
"I feel like I'm in good shape. I've just been working out like an animal. I've got nothing else to do. As far as being in physical shape I'm ready to go."
More than anything, Best said he couldn't wait for the day when reporters are surrounding his locker to talk about football and not concussions.
"That'll be a good day and hopefully (it's) Monday night after the game."