Knox had been with the Bears since the team took him in the fifth round of the 2009 NFL Draft out of Abilene Christian. He's been a productive player for the team, but suffered a significant injury in the 2011 season that saw him sit out the entirety of this past season on the PUP list.
The play that injured Knox occurred on Dec. 18 against the Seattle Seahawks. Knox fumbled on a 17-yard reception over the middle, and as he turned back around to try and get back to the ball, he was hit hard by Anthony Hargrove, a defensive end. Knox bent back and was down on the field for almost 10 minutes before being removed on a backboard.
From there, he was taken to a hospital where he had surgery, and he hasn't seen the field since. In the leadup to the 2012 season, there was little doubt that Knox would begin the season on the PUP list. He did, and didn't come off of it once.
Interestingly, this meant that the Bears could keep Knox through the 2013 season, despite his contract set to expire on March 12, the beginning of the new league year. Players that spend an entire season on the PUP list can be tendered a contract of the same amount to make up that missed year.
However, the Bears have granted him his release, so they obviously didn't feel that this was a viable option. His contract number would have been south of $1.5 million had they kept him. Knox recently spoke about his rehab on the Bears' official website in December, where he expressed his desire to remain with the team.
This article didn't include any information on where Knox is exactly in his rehab, save for the fact that Knox is keeping his goals in the short-term, which can't bode well for his potential readiness for next season.
When healthy, Knox is a strong receiver. He doesn't have much of an actual injury history, as just about any player in the league would have been put down big time by the hit from Hargrove. In 2011, he was leading the Bears with 37 receptions for 727 yards and a pair of touchdowns when he went down with the injury
Before that in 2010, Knox had 51 receptions for 960 yards and five touchdowns playing in all 16 games. In his rookie season, he had five touchdowns and 527 yards. He's also a valuable kick returner, with 927 yards and a touchdown in his rookie season, and 397 yards before being injured in 2011.
Knox is a strong deep threat with solid hands and of course, he's still young at 26 years old. But he is coming off a major debilitating injury, and he will absolutely have to start back at the bottom and work his way up. If he's healthy though, smart money is on him finding a team as soon as he has the green light to play, as his potential is still plenty high.