The team later confirmed the suspension, which was for conduct detrimental to the team.
The news came after a day that included a flurry of developments concerning Dolphins offensive tackle Jonathan Martin's absence from the team. Martin, who left the team last week after an emotional breakdown, is expected to be placed on the non-football illness list this week.
Incognito is at the heart of the NFL investigation into what happened, Darlington reported on NFL Network's "NFL GameDay Final."
One issue, according to a source close to Martin, was the $15,000 that teammates expected him to pay for a Las Vegas trip that he didn't attend, NFL Media's Albert Breer reported. Other reported instances were captured in voicemails and texts.
The second-year pro shared the voicemails and texts with his parents Saturday, turning them over to the Dolphins and the league Sunday, sources close to Martin and involved in the investigation told Breer. The evidence implicates Incognito and, to a lesser extent, center Mike Pouncey. In one voicemail, in particular, Incognito used a racial slur and threatened violence.
"We received notification today from Jonathan's representation about allegations of player misconduct," the Dolphins said Sunday in a statement. "We are taking these allegations very seriously and plan to review the matter further. We have also reached out to the NFL and asked them to conduct an objective and thorough review. As an organization, we are committed to a culture of team-first accountability and respect for one another."
The NFL has been in contact with the team on the matter, but the suspension came from the team.
"We have been in contact with the team on this matter since last week and we will conduct a thorough review," the NFL said Sunday in a statement.