The usual sharp edge between these old rivals was missing for an hour until Bristol Rovers' Ali Gibb floated in a long cross which became a corner.
Christian Edwards came up from the backline to head in the set piece and the game was suddenly alive.
Even more so minutes later, when a mistake by Edwards allowed Glynn Hurst to steal an equaliser as he met Paul Bolland's cross from the right.
However, Rovers, who had been struggling until their goal, went on to take the points. Junior Agogo, racing onto a ball from Stuart Campbell, clipped the winner with the outside of his right foot.
It was his third goal of the new season and his exuberant celebration brought him a yellow card.
After drawing their first two games since relegation Notts had set out to assert themselves.
For a long time in the first half Rovers hardly had a meaningful kick and could've been two behind when they failed to deal with Matthew Gill's long throws.
From the first Hurst should have tucked the shot away and from the next John Anderson thumped a shot from Mike Edwards off the line.
It hardly got better for Rovers because their keeper Kevin Miller was often reluctant to come of his line and caused uncertainty in defence. Miller's dithering could have seen County go ahead just before the break, but he redeemed himself by spreading expertly to deny Gavin Gordon.
Notts were always close marking danger man Agogo and it took the urgings of manager Ian Atkins in the half-time dressing room to give Rovers a greater sense of urgency.
Agogo stepped up his running, but this was always a game looking for a touch of control and inspiration and this was a long time coming.