THREE trips to the sin bin resulted in Pewsey playing with 14 men for nearly half their Dorset & Wilts One North match.
Trowbridge started strongly and a penalty and converted try gave them the early advantage.
Pewsey scrum-half James Haynes landed a penalty, but Trowbridge added two more converted tries to pull further clear.
Vale rallied, but a further Trowbridge score left them 29-3 ahead at half time.
Pewsey came out firing on all cylinders and were rewarded with a try from centre Chris Spence who split the defence with a dynamic run, converted by Haynes.
With Vale enduring card trouble after the break, the visitors scored two converted tries but, with 14 men, Vale came back strongly and with ten minutes to go Haynes went in for a try, which he converted.
Both sides traded scores late on, Pewsey lock lock Olly Spence scoring from a free flowing movement.
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