Because we do not have our first choice, England international, left back playing, but our League 1 left back playing, so Barnes needs to cover for him, which Dobbie would not be good at doing. Tis the best option for today.
I know I will get pulled up for saying this, but why drop a guy who has got two in two and has just started to get his confidence back. He's a guy who plays and thrives on confidence and has started to look dangerous.