He got a red card. If they gets a red card you are stuck with them for that round, and they can not be substituted or hand over captaincy to someone else.
I had both Suarez (captain) and Felipe Melo yesterday. Three red cards for me so far. Gourcuff was the first.
Thanks - Makes sense now I suppose
Annoying that my captain is stuck on player that got 2 bloody points, and that I can only play two of Higuain, Tevez and Villa.