It was their second victory in a row after beating Exeter Athletic 27-5 the week before in the league.
Tries by Tina Martin and Liv Verner and two penalties from Verner had put Services good position, but Yeovil came back and set-up a nerve-wracking ending. However, Devonport’s defence stood firm and they were able to progress in the cup.
The day before, Championship South West Two side Plymouth Albion beat lower league neighbours Plymstock Albion Oaks 29-0 in the RFU Intermediate Cup at a rain-soaked Brickfields.
Oaks, who are in their first season in NC One South West, battled really hard in the first half and were only 10-0 down at the break. But Plymouth’s higher league experience told in the second period and they pulled away.
Albion will now visit league and Devon rivals Cullompton in the next round on December 15.
All three Plymouth women’s teams will be back in league action this coming Sunday. Albion will host Newbury, Plymstock Albion Oaks will entertain Chew Valley, while Services will travel to Bideford.