Lee Johnson was victorious in the Johnson versus Johnson clash at Boundary Park.
Lee's Oldham Athletic side beat his father Gary's Yeovil Town team 1-0 after a goal by Matt Smith on the stroke of half-time.
Oldham's win sends Portsmouth and Hartlepool down to League Two and moves the Latics further away from the relegation zone.
Yeovil's defeat dents their hopes of winning automatic promotion, but they are still guaranteed a play-off place.
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An overcast start with cloud spreading from the east to Devon and Cornwall. Cool winds and isolated showers in parts of South Devon
An overcast start with plenty of cloud filling in from the east. Some isolated showers in Somerset and Dorset. Highs of 8 or 9 degrees.
Temperatures will drop down tonight and tomorrow isn't great with the prospect of more cloud, showers and north easterly winds.