Banfield's winner came on 26 minutes before he was then shown a straight red card with twelve minutes remaining. Team mate Kieran Cooper's second yellow near the end reduced the hosts to nine men but the visitors couldn't take advantage and slipped to defeat.
Hallen remain in fourteenth position while Hengrove stay in 19th position, a point ahead of Gillingham Town who now have three games in hand. Next up this weekend is the trip to Wincanton Town, firmly ensconced in the playoffs.