Bellerin slid the ball just wide from Ozil's
delightful ball over the top of the defence, before Giroud made it 3 - 0 with a superb curling effort from inside the box after being found by fellow substitute Alex Oxlade - Chamberlain.
Yaya Toure found David Silva with a
delightful flicked pass
over the
top and when Barnsley goalkeeper Luke Steele pushed the Spaniard's volley onto the post, Tevez was on hand to tuck the
ball home.