Ciaran McGuckin scored the only goal as Yeovil leapfrogged opponents Dagenham & Redbridge in the Vanarama National League table.
Visiting goalkeeper Elliot Justham was busy in the first 20 minutes, saving from Jordan Young, Frank Nouble and McGuckin, who moments earlier had had treatment for an injury.
It remained goalless until the interval, but McGuckin broke the deadlock with a 55th-minute header before quickly having another shot saved.
Brett McGavin twice went close to a second and there was no way back for the Daggers despite six minutes of stoppage time.
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