Brazil forward Gabriel Jesus opened the scoring midway through the first half in London before Sterling took over, scoring three goals in the second half as the champions started their title defence in ominous form.
Sergio Aguero was the other goalscorer, opening his account for the season from the penalty spot in the closing minutes of the game.
“The most important thing was to start well and get the win. Once the second goal went in I thought we were brilliant,” Sterling told BT Sport.
“It was quite difficult in the first half. Some of our touches were sloppy but once the team got into a rhythm the passes came and more chances came.
“With the players we have here there are competitions in training every day. It’s a joy to put the ball in the back of the net.”
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