Earlier in the day, the team explained that O'Dea had gone back to Toronto to finalize a deal.
Defender Steven Caldwell wore the captain's armband in the loss to Kansas City.
O'Dea has one goal and one assist through 17 games with TFC this season.
He last played for Toronto on July 3, a 3-3 draw with the Montreal Impact at BMO Field, where he scored his only goal for TFC this year.
O'Dea began his career with Celtic FC in the Scottish Premier League in 2006 and has represented Ireland at the under-21 level and at the senior level.