[FMH for iPhone] In-game tactics conundrum

Please tell me if I'm being stupid, but here's what happened to me during a game...

My defender gets sent off, so I decided I would take off a midfielder and bring on another defender. So, I made the substitution ok, but how do I move the player I brought on into defence?

I can't see the formation screen, only the list of players and substitutes. If I try to drag the defender I brought on over to the defender who got sent off (to switch their positions) nothing happens, and the player I brought on remains a midfielder.

How do I switch a player's position during a match???

try swapping the positions before the substitution.

Thanks, it worked!