Definitely, but will he play him in his best position (centre mid)? Bear in mind that would mean dropping Doyle (never going to happen) or Rose (probably never going to happen).
We're crying out for someone in the centre of midfield to play a bit closer to the front two, and O'Brien is the perfect player to do that. But Ardley seems wedded to this bizarre defensive 442, with both CMs playing as holding midfielders.