From the beginning, there always seemed like a demarcation line of concern when it came to the ongoing contract discussions with Detroit Lions defensive tackle Ndamukong Suh.

Even though he switched agents this offseason and there always appeared to be something keeping negotiations between Suh and the Lions from progressing, there was optimism the two sides would come to a deal by the time training camp started.

Training camp begins Monday with veterans reporting Sunday. And now colleague Chris Mortensen is saying a team source told him the team is not optimistic about reaching a deal by the start of camp.

With it, the Lions can officially become concerned about whether or not Suh will be with the team beyond this season. Suh has seemed like a player who would not want to have contract discussions during a season, especially if he is now potentially playing for a new deal either with Detroit or elsewhere.

It would behoove the Lions to say they would not negotiate during the season. Doing so gives a timeline for any real negotiations and eliminates what would otherwise be a constant distraction for a franchise needing to minimize them at every possible cost.

This leaves Detroit and the Suh’s agent, Jimmy Sexton, with two potential windows to hatch a deal -- if there is even the true desire to do so: Either between the start of training camp and the beginning of the season, or between the end of the season and the start of free agency.

If the Lions were smart, they would push to not have Suh play out the season with free agency looming. Another huge season from him and he may want to test free agency no matter what, just to see what he could command on the open market as one of the top players at his position.

Either way, the concern about Ndamukong Suh is now real and it should lead to an interesting few weeks as a sidebar to Detroit’s training camp.

This also sets up one of the worst-case scenarios for Detroit when it chose to decline the fifth-year option on fellow defensive tackle Nick Fairley. If Suh does not get a deal done, there is a real chance the team could lose their first-round picks from 2010 and 2011 after 2014.

It would decimate the interior of a defensive line the Lions built around the past few seasons.

Of course, the Lions can keep Fairley around by either tagging him or re-signing him if he has the season Detroit is hoping for.

None of this is to say Suh is wrong at all. He has every right to have his agent negotiate the best possible deal for him considering the finite nature of his profession. It is exactly what Suh is paying Sexton for.

But if Suh really wants to be in Detroit and really wants to help the Lions turn into a winning franchise, he would push his agent to finish a deal before Sept. 8, when the Lions play on "Monday Night Football" against the Giants.