The Tanners took charge of proceedings from the start, though it took them 26 minutes to break the deadlock.
Tommy Hutchings did the trick, sweeping home the loose ball after experienced Horley keeper Ian Chatfield blocked a shot from Greg Andrews, who is pictured (courtesy of Andy Nunn) celebrating with the gaolscorer.
Charlie Holness drilled home a low shot from 25 yards to double the lead on 37 minutes, looking rather surprised by his own expertise.
Horley rallied briefly after the interval but Tanners wrapped it up with a comical goal in the 77th minute. A Horley defender ducked low to allow a long ball forward to bounce through to Chatfield.
But he misjudged the flight and the ball landed on his rump before dropping into the path of Andrews, who made no mistake.
Tanners now host Tooting, whom they have already beaten 3-0 away from home in a Ryman South fixture this season.
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