Florida's Sun Sentinel is reporting that Miami Dolphins coaches asked lineman Richie Incognito to "toughen up" teammate Jonathan Martin, according to more than one team source. As reported by Omar Kelly: The sources told the paper they believe that Incognito, who is accused of using racially incendiary language and bullying tactics against Martin, may have taken those orders too far.

It's not clear whether those marching orders will now become part of a pending investigation by the NFL into the Dolphins' locker room culture, and the alleged bullying that took place between Incognito and Martin.Incognito has been suspended indefinitely by the Dolphins for conduct detrimental to the team for his tactics involving Martin, the team's 2012 second-round pick, who left the team last week and later accused the Dolphins of having an unsafe working environment.

Martin's smoking gun is a threatening, and racially offensive voice mail Incognito left him in April. In that voice message Incognito calls Martin, who is bi-racial, a "half n-----," threatened to slap his mother across the face, and uttered the words "I'll kill you."

Sources say that communication took place when Martin skipped two days of the team's OTA program, and Incognito was encouraged by his coaches to make a call that would "get him into the fold," one source said.

Even though OTA workouts are voluntary, the NFL culture forces coaches to strong arm the team's leaders to make sure everyone attends. Sources say Incognito was doing his job, but they admit he crossed the line.

Paul Steinbach is Senior Editor of Athletic Business.