The NFL Players Association is looking into Jonathan Martin's situation in Miami, but has not launched an investigation into possible harassment of the offensive tackle by his teammates.
Martin left the Dolphins on Monday to receive help for emotional issues, and it's unclear whether he's expected back. The Dolphins are off this weekend.
In a statement released Saturday to The Associated Press by the union, the NFLPA stressed its concern about players being provided a "safe and professional workplace." Martin reportedly left the Dolphins because of the way teammates were treating him, with guard Richie Incognito cited in one report.
"We have an obligation to protect and support all of our members," the statement said. "We take official investigations very seriously and in this case, we have not launched an investigation into Richie Incognito or other players in Miami.
"The NFLPA believes that management has an obligation to ensure a safe and professional workplace and we will continue to be in close touch with our player leaders and all players involved as the information develops."
A person familiar with the situation told the AP earlier Saturday the NFLPA plans to look into the matter next week. The person spoke on condition of anonymity because the Dolphins have said little about the reasons for Martin's absence.
The Dolphins have attributed Martin's absence to a non-football illness. The second-year pro from Stanford played in Sunday's loss at New England, then missed practice this week and sat out Thursday night's victory over Cincinnati.
The win snapped a four-game losing streak that had stirred talk of dissension between coaches and among players. When asked Friday if he has seen evidence of bullying or harassment, coach Joe Philbin said: "This is something we take very seriously, and it will not be tolerated."