When the NY Jets signed Chris Johnson this offseason it was often said the Jets signed the best free agent running back available. Many thought he would provide the kind of big play ability that has been greatly lacking in the Jets' offense the last few years. Some even thought Johnson still had several 1000 yard seasons left in him and would likely be enshrined in the Hall of Fame when his playing days were finally over. As of now, none of those things appear to be true.

Chris Johnson is an unusual NFL running back. He doesn't have great size. He doesn't have great power. He isn't particularly shifty. He doesn't possess great field vision. The truth is, even at his best Johnson really had only one exceptional talent: he was fast. But, oh what a talent that was! He wasn't just fast, he was blazingly fast, possibly the fastest running back ever to play in the NFL. This world class speed allowed him to do one thing really well. He was a great one cut and go runner. He could hit a crease and explode through it better than any back in the league. He couldn't break tackles, he couldn't make guys miss all that well, but boy could he see a hole and explode through it. This one talent allowed him to have an extraordinary 2000 yard season while averaging 5.6 yards per carry in 2009. That is a long time ago now.

Today Johnson is a back with more than 2000 touches and more than 10,000 yards of wear and tear on his body. He is now 29 years old, on the cusp of old age in running back years, and it shows. Johnson has had a league average or below yards per carry number in three of his last four full seasons, and at 4.1 ypc this year, he is on track to make it four out of five. Johnson also is averaging a career low 5.0 yards per reception, an area where he was supposed to bring the Jets an added dimension but has largely failed to do so. Watching Johnson play you don't get the sense you are watching a player with extraordinary speed, explosion, or anything else anymore. What you see is largely an ineffective running back. A back who gets stuffed at the line more often than he breaks one. A back who lacks the one thing he once had that made him special: game breaking speed.

Consider how Johnson has done in terms of big plays; i.e., running plays of more than 20 yards. So far Johnson has one running play over 20 yards in 2014, tied for 17th in the NFL and on pace for 4 such plays for the year. In 2013 Johnson had 5 big plays. In 2012 it was 8. In 2011 Johnson had 11 big plays, in 2010 it was 13, and in 2009 he led the NFL with an extraordinary 22 big plays, nearly doubling the second place running back that year. What is apparent is a slow, steady deterioration in Johnson's big play ability. His 2013 total tied with six other players for 17th in the NFL, just a bit below average for a starting back. If he ends up with 4 or fewer in 2014 he will likely rank towards the bottom of NFL backs this year.

With other backs with other skills this steady decline in big play ability might not matter so much, as they bring other things to the table. But Johnson has always been something of an all or nothing back. What he has brought to the table in the past has been big play ability and little else. When the big play ability is gone, as it appears to be, we are left with simply little else. Even in his one big play this year, his 35 yard TD run against the Lions last Sunday, there was little in the way of explosion or elite speed in evidence. To his credit Johnson kept his legs churning in traffic until a huge gap opened up, which he ran through all the way to the end zone. But watching the play you did not see Johnson demonstrate elite acceleration and pull away from defenders like they were standing still, you did not see him bursting through a crease a lesser back could not have exploited. Rather, you simply saw him take advantage of a huge hole that opened up in traffic, a hole that likely any back on the Jets and most backs in the league would also have scored with. In short, the one big play Johnson has was not so much a product of his unique skill set as it was a chance encounter with a big hole. He kind of lucked into a situation most NFL backs would have taken to the house.

Johnson is the only one of the Jets three back rotation that does not have a 20+ yard reception this year. Johnson's longest catch this year went for a paltry 12 yards. In addition, Johnson currently has the lowest per carry average among the three Jets backs with 4.1 yards per carry.

Given Johnson's long decline in big play ability, his failure to achieve even NFL average yards per carry numbers this year and in 3 of the prior 4 years, his inability thus far to generate anything in the passing game, and his propensity to be stuffed at or behind the line of scrimmage more than any other back on this team, it is fair to ask, is Chris Johnson done? From what we have see of him this year, his lack of elite speed, his lost explosiveness, his overall mediocre performance, I think the answer is probably yes, he is. Given the fact that his compensation is now fully guaranteed for the 2014 season it is highly unlikely the Jets will cut Johnson before the end of 2014. However, if his play does not considerably improve, I think he is demonstrating not only that Bilal Powell deserves to supplant him on the depth chart, but also that Johnson probably should not be on the 2015 Jets roster. In 2015 Johnson will be due a base salary of $3,500,000, none of which is guaranteed, along with prorated dead money of $1,750,000 from his signing bonus. Unless Johnson's level of play picks up considerably in the last 12 games of 2014, Chris Johnson is simply not worth anything close to $3,500,000, and he should not be a member of the 2015 Jets. Running back is a very tough position that takes a heavy toll on the body and results in very short careers. Unfortunately for the Jets and Chris Johnson, Johnson's useful career appears to be all but over. If Johnson is not a member of the Jets in 2015, you can count him among the growing list of free agent failures John Idzik has signed, as he would have cost the Jets $4,500,000 for one very mediocre year.