Goals in either half from recent loan signing Jordy Mongoy proved enough for the Mariners, who bounced back well from their 3-2 league defeat at Warrington Town last weekend.
Rick Smith headed home a consolation for the hosts five minutes from time, but they were unable to find a leveller at the Neuven Stadium.
The result means Kevin Phillips' Shields move a point above previous leaders Gainsborough Trinity, with two games still in hand on the Holy Blues.
Results - Wednesday 30 November
Radcliffe 1-2 South Shields
Photo credit: Kev Wilson / South Shields
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