The NFL sent all 32 teams a letter Monday voicing the league's displeasure with the handling of the three-day tampering period. Now the Miami Dolphins are worried that they will be the target of league investigations for their handling of the pursuit of defensive tackle Ndamukong Suh.

The "legal tampering period," which was instituted in 2013, allows teams to negotiate with impending free agents three days before they are set to hit the open market; however, no contract terms are to be reached. That rule has seemingly been broken by multiple teams prior to the 2015 NFL free agency period, including the Dolphins, who reportedly agreed to a six-year, $114 million deal with Suh on Sunday.

According to Armando Salguero of the Miami Herald, the Dolphins are now in the league's crosshairs for breaking the rules of the tampering period and team officials are "nervous" about a potential investigation.

When Chris Mortensen of ESPN broke news of the deal, it had some specific contract figures, including $58 million guaranteed and $60 million in the first three years of the agreement. Assuming Suh signs with the Dolphins, if those numbers from Mortensen's report on Sunday are accurate, it will be hard for the team to argue that no contract figures were in place prior to the beginning of free agency on Tuesday afternoon.

The Dolphins aren't the only ones either, although no team will give out a blockbuster deal in free agency quite like the one Suh is set to receive. Still, Byron Maxwell, Pernell McPhee and Jeremy Maclin are just a few of the other players with deals reportedly in place that have included contract figures.

Per Salguero, punishment from the league for teams found to be in violation could range from fines to the loss of draft picks.