After weeks of rumors that it might happen, the Union made it official on Friday that top assistant coach Mike Sorber has left to join the staff of MLS expansion team Los Angeles FC.

Reports of Sorber's potential departure first surfaced in late October. At the time, Union sporting director Earnie Stewart said publicly that Sorber hadn't yet told the team he was going to leave, but also didn't say Sorber was absolutely staying.

Sorber was known for taking charge of many practice sessions. He also had a bit of a reputation as the bad cop on the staff. But he backed it up with considerable experience as a player, having been part of the U.S. national team from 1992 to 1998. He played 67 games for the national team, and was teammates with Stewart on the 1994 World Cup roster.

If it wasn't surprising that Sorber left, it also wasn't surprising that LAFC was the destination. The new team's coach is former U.S. national team head coach Bob Bradley, who managed Sorber when he played for the Chicago Fire in 2000. Bradley also had Sorber on his U.S. national team coaching staff from 2007 to 2011.

The Union hired Sorber before the 2014 season, when John Hackworth was in charge. When Hackworth was fired that summer, Sorber was passed over for the head job despite having more bench experience at the time than Jim Curtin, who got the role. Curtin kept Sorber as one of his assistants. Both men were products of Bradley's coaching tree, as the Fire drafted Curtin the year after Sorber ended his playing career.

"We'd like to sincerely thank Mike for his contributions to the Union and wish him all the best moving forward," the Union said a statement. "We are currently conducting a coaching search to fill the vacancies on our staff, and will make announcements regarding any new hires in the near future."