First-half goals from Jonathan Franks and Richard Hinds set the Glovers on their way before substitute Michael Woods added another after the break. Dale's pressure brought a consolation goal when Grounds put the ball past his own goalkeeper.
Franks got his goal after seven minutes when he picked up a poor backpass from former Yeovil player Kevin Amankwaah and rounded the keeper.
After 29 minutes a free-kick on the right by Josh Morris was headed on by Paul Huntington and his central defensive partner Hinds finished to extend the host's lead.
Glovers boss Gary Johnson introduced Chelsea loanee Woods midway through the second half and he scored his first ever senior goal when Andy Williams picked up a clearance from keeper Dave Lucas and crossed for Woods to touch in from 10 yards.
Rochdale were rewarded for their consistent pressure when Grounds hooked into his own net while attempting to clear the ball.