Good question.
I suppose Jan is the closest we have to a proper leader. Unfortunately, he appeared disillusioned playing at LB before his injury and one hopes that the arrival of a new manager will restore faith in our club. Would make him our captain in a heartbeat.
I think Jan is a magnificent player but I get the feeling that Jan's priority is...Jan. Sulking at playing LB doesn't make me think he's a team player.
Shame Sandro's English isn't a wee bit better as I think he'd be a great motivational captain.