Davis, Mendes and Ferguson, while all good players, are all right of centre midfielders. So naturally they tend to play very narrow. Davis is playing right midfield at the moment out of necessity, however he is far more effective tucked in. Ferguson is playing the left central role that Kevin Thomson fills superbly.
It's no coincidence that Rangers have won all five Old Firm clashes that Kevin Thomson has played in since he joined Rangers, and lost all three that he has missed. He does so much for the team, all the dirty work, the sort of job that Stuart McCall used to do.