The person confirmed the upcoming meeting to The Associated Press on condition of anonymity because the league and team haven't announced the details of the investigation.
Meeting with Martin will be Ted Wells, a senior partner in a New York law firm with experience in sports cases. Wells was appointed Wednesday by NFL Commissioner Roger Goodell to investigate possible misconduct in the Dolphins' workplace and prepare a report that will be made public.
Dolphins guard Richie Incognito was suspended in the wake of allegations by Martin, who is with his family in California to undergo counselling for emotional issues. Wells is investigating whether Incognito harassed or bullied Martin, and whether their teammates and the organization mishandled the matter.
Incognito has long been regarded as among the NFL's dirtiest players, and has had brushes with the law. A police report that surfaced Thursday said a female volunteer at a Dolphins charity golf tournament in May 2012 complained that Incognito harassed her. According to the report filed in the Miami suburb of Aventura, the woman said Incognito touched her inappropriately with his golf club, leaned close to her as if dancing and then emptied bottled water in her face.
Incognito was not charged. The Dolphins declined to comment Friday.
The Dolphins (4-4) will play for the first time since the scandal broke Monday night at Tampa Bay (0-8). At least 75 reporters and cameramen tracking the case were in the locker room after Thursday's practice, but receiver Brian Hartline said the scrutiny won't prevent the team from playing well.
"It almost heightens your awareness," he said. "You know it's going to take away from your focus, so it does the exact opposite. You overcompensate to make sure you stay aware of the game."
Dolphins players have robustly defended Incognito, praising his loyalty and leadership even though he's now a notorious national villain. They've been less passionate in their support of Martin, saying he and Incognito behaved like best friends.
While Martin has been a starter since the first game of his rookie season, he developed a reputation in the NFL for lacking toughness. That impression might have been reinforced by the way he handled his issues with Incognito, current and former teammates acknowledge.
"A lot of people might look at Jonathan Martin and think that he's soft because he stepped away from the game, and say, 'Why don't you just fight him?'" said Seattle Seahawks receiver Doug Baldwin, who played with Martin at Stanford. "Well, if you look at it with common sense and being logical, what options did Jonathan Martin have?
"He could fight Richie Incognito. He could go and tell on the players, which we know in the football locker room doesn't go over too well. Or he could remove himself from the situation and let the proper channels take care of itself. And I think he made the intelligent, smart choice without putting himself or Richie Incognito's physical abilities in danger."
AP Sports Writer Tim Booth in Seattle contributed to this report.