A weakened O's could only name one sub for the trip to Somerset and they were further hampered when Tom Morgan received his marching orders on eleven minutes for kicking out.
It was the start of a horror show for the visitors as Wincanton scored five times in a one sided first half at Moor Lane. After the break, Oldland played better but conceded twice more to complete a real humbling.
Next Saturday, the O's host Portishead Town at Castle Road in the final game before Christmas.