If you're one of 10 outfield players picked in a game your team dominates about you offer no meaningful contribution then you've done terribly. Football is a proactive game, you actually have to do things. Shaw did nothing all game, Rojo was a bigger threat down the left than Shaw today. The only player who can get away with being completely innocuous today is De Gea because the ball didn't go near him.
When a fullback isn't being asked to defend then it isn't enough to just sit in line with the centerbacks and do nothing, he should have been standing on the touchline 20 yards further forward and stretching play.