Kent Langridge scored twice, but his brace came as little more than consolation for Winchester, who lost 5-2 as Oxford Hawks surged to the top of South Premier Division 1.
Winchester enjoyed the majority of possession in the opening stages, but Oxford gradually began to assert themselves and after a fine short corner save by Ben Cowling, Jack Biggs fired Hawks into a half-time lead.
An Andy Watts double early in the second half gave Hawks a 3-0 lead before Langridge cut the gap.
Watts completed his hat-trick before Langridge clawed it back to 4-2. Matt Wood got a fifth for Oxford, who included Winchester raised Ed Ellis in their ranks.
Trojans lost 3-0 at West Hampstead in SPL2.
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