Paul Scharner was West Bromwich Albion's match winner as the Baggies beat 10-man Aston Villa 2-1 on Saturday to secure their first away league win over their local rivals for 32 years.
Alex McLeish's side went ahead through Darren Bent's penalty at Villa Park, but the derby swung West Brom's way when Villa midfielder Chris Herd was controversially sent off following a clash with Jonas Olsson inside his own box.
Chris Brunt missed the resulting penalty but the Baggies equalised through Olsson before half-time and Scharner netted the winner after the break.
The victory gave Albion a second dose of derby delight after last week's triumph over Wolves and Roy Hodgson's side have collected 11 points from the last six games.
It was Villa who had the better of the opening stages and England striker Bent squandered a golden chance to open the scoring after five minutes.
Barry Bannan failed to make proper contact on his shot but it fell straight to Bent unmarked eight yards out and he somehow scooped his shot over the crossbar from close-range.
Villa took the lead after 23 minutes after a mix-up between Steven Reid and goalkeeper Ben Foster.
Reid tried to chest the ball back to Foster but Gabriel Agbonlahor nipped in and was brought down by the on-loan Birmingham goalkeeper.
Bent stepped up to send Foster the wrong way from the spot but it wasn't long before referee Phil Dowd made his crucial intervention.
Herd had impressed in midfield for Villa until the 34th minutes when he became embroiled in an off-the-ball clash in the penalty area with Olsson.
It looked a minor incident but Dowd brandished a straight red card before pointing to the penalty spot.
Villa had a let-off as Northern Ireland midfielder Brunt drilled his spot-kick wide and moments later Shay Given produced a fine save to keep Villa in front when he turned aside a shot on the turn from Somen Tchoyi.
But a minute before half-time Olsson brought the Baggies level when he outjumped the Villa defence to head home Brunt's corner.
Albion tried to make their numerical advantage count after the break and Given parried away a fierce drive from Youssouf Mulumbu.
Olsson again climbed above the Villa defence in a replica of Albion's equaliser but this time he headed Brunt's corner over the crossbar.
The visitors were not to be denied and after 57 minutes Scharner put them ahead with Villa again caught out at a corner.
Agbonlahor failed to deal with Brunt's corner at the near post and Scharner reacted in an instant and volleyed home via the underside of the bar.