Tony Pulis admitted that his West Brom side had used his inside knowledge of former club Crystal Palace to find a way of beating the Eagles at Selhurst Park.
An early James Morrison header put the Baggies in a strong position and they defended well as Palace looked to hit back, wrapping up a vital win courtesy of a Craig Gardner strike; Pulis's men move eight points clear of the relegation zone.
It ended a four-game winning streak for his former side as the Welshman enjoyed victory on his first return to south London since his departure on the eve of the campaign.
With the Palace squad little-changed since then, new Eagles boss Alan Pardew said leading up to the game that Pulis's inside information would give the Welshman a "huge advantage" - and the West Brom manager revealed that his side had worked on things in training that could give them the edge.
"We worked on a couple of things in respect to what I thought Palace would do," he said. "We scored from a corner that we have worked on, which was really pleasing. I thought we should have had a penalty in the first half and then Gardner's strike to make it two-nil was crucial really in lots of respects.
"We were resilient and defended well and in the end I thought we deserved the points."
Pardew tasted defeat for just the fourth time in the league since taking charge at Palace and conceded that his players had been caught out by Pulis's awareness of their short-comings."That was a weakness in our set up that Tony exploited," he said.
Sunday Indo Sport