Myles Jack's NFL career has yet to begin, and some are already mourning it. Despite a serious knee injury early in UCLA's 2015 season, Jack remained one of the most exciting prospects through the early portion of the 2016 NFL Draft process, As he worked his way back to health, Jack's already ample stock continued to rise.

But then came the medical checks and re-checks. And now, Jack's stock may have plummeted to the point that some teams are planning to avoid the two-way Bruins star altogether.

Jack, likely sick of hearing talk about his injury and the state of the meniscus in his right knee, offered a promise - more of a threat, actually - to teams that choose to bypass the opportunity to select him Thursday night.

"If people look into that, I would advise them not to," Jack said. "I've been doing workouts with teams and they've said I'm fine. Doctors have said I'm fine. It really just comes down to whatever team is comfortable picking me. It's one of those deals where, if you want me you want me. If you don't, I'm going to make you pay."

Unfortunately, the list of teams that are planning to skip out on Jack in the first round seems to be growing. Some, like the New York Giants at No. 10, never would have had an opportunity to land Jack prior to his injury. But now, it's entirely possible that he makes it to them, and with a glaring need at linebacker, it would make ample sense for the G-men to go that direction.

Unless they're convinced Jack's not worth it.

Even Jack himself acknowledged recently that the issues with his knee warrant at least some caution, telling a reporter that the degenerative issues are there but that no one knows what that means or when it will become an issue.

"Down the line, possibly I could have microfracture surgery - potentially. Who knows what will happen? Nobody knows how long anybody will play in this league," Jack said, adding that playing three years in the NFL would be considered "above average."

Jack is right there, but that's not the kind of bet-hedging that teams, ready to expend a first round pick, are going to want to hear. Teams want long-term starters early in the draft. A guy who may not last beyond NFL year three?

That may not even be worth a late-round flier to some.

Jack's almost immeasurable talent will ensure that he gets drafted, and likely highly. However, his career and his knee - that "time bomb" - will be watched closely by those organizations that deemed him simply too much of a risk.