The England international was lucky not to be ruled offside for City’s opener as the ball ricocheted off Sterling from Daryl Janmaat’s attempted clearance and into the net a minute into the second-half
Sterling then rounded off a characteristically slick City move four minutes later and completed his hat-trick in style on the hour mark before Gerard Deulofeu pulled a goal back just 22 seconds after coming on as a Watford substitute.
Liverpool can cut the gap to a point with victory over Burnley on Sunday.
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