Fire center back Arne Friedrich returned to Germany Tuesday to work with his therapist, Thomas Fennewald, to get treatment for hip tightness.
Friedrich isn't expected to return to Chicago until July 1.
The German World Cup veteran spent two weeks in Germany earlier this season to get work with Fennewald after he sustained a strained hamstring in the days leading up to the season-opener. Fennewald has worked with Friedrich for nearly a decade.
Friedrich has yet to appear in a match for the Fire this season. He was successful in rehabbing his hamstring. But just a few days after he had returned to training, Friedrich sustained the most recent hip injury.
He has since been seen kicking a ball around on the sidelines during training, but has not participated in team activities even as a limited participant.
While the Fire appears to remain committed to Friedrich, it is clear his return this season has come into question. Last week the Fire traded for center back Bakary Soumare who has assumed Friedrich's role as one of the team's two starting center backs.