I think the only true aggrievance is Maguire's red - he should've been sent for violent conduct. Maguire's reaction saves him big time and even calmed the Chelsea bench down.
Otherwise, Giroud was offside (wasn't as close as many we've seen this season) and Azpi totally pushed Williams. What Fred does to Azpi isn't a foul anyone else on the park, and two handed pushing someone in the back is.
Fundamentally Chelsea couldn't put the ball in the goal which is the same problem they've had against us all season.