Chris O'Grady returned to haunt his old club as Rochdale won 2-1 at Oldham in League One on Monday afternoon.
The former Latics striker bagged both goals in the second half at Boundary Park to punish bad defensive errors.
Dale Stephens twice went close for Oldham and Jason Kennedy headed over for Rochdale before Filipe Morais forced the first save of the game from Josh Lillis from long range after 52 minutes.
Rochdale went ahead after Reuben Hazell was penalised for a shove on Craig Dawson and, after Gary Jones slammed the resulting penalty against a post, O'Grady converted the rebound.
It was 2-0 after 76 minutes, with O'Grady seizing on a woeful back pass by Hazell and calmly slotting inside the far post from 10 yards.
Dale defender Scott Wiseman received a very harsh straight red card for a foul on Cedric Evina after 85 minutes, and Oldham were inspired into staging a late rally which saw Dean Furman volley in from 14 yards.