Substitute Lee Tomlin’s stunning free kick gave Cardiff City the three points on a bitter night in the Welsh capital.
Callum Paterson poked home from close range to give the hosts an early second-half lead before Charlie Austin drew the visitors level from the penalty spot.
But it was Tomlin who once again proved the difference for the Bluebirds as his free-kick gave the hosts a first league victory of 2020.
Story of the game
There was little for fans of either side to shout about in the first 45, with chances few and far between.
The best chance of the half came in the opening exchanges as Will Vaulks did well down the right hand side, his ball found Robert Glatzel in behind but the big Frenchman rushed his shot as the chance went abegging.
The visitors first half chance of the game came in the 18th minute when a corner was half cleared to Jake Livermore on the edge of the box. However he fizzed his first time effort wide of the target.
As the half began to draw to a close there was another opportunity for the visitors to take the lead. Baggies winger Kyle Edwards showing some decent footwork to get to the byline and pick out Dara O’Shea at the back post.
His effort flew high and wide as the half drew to a close with the scoreline goalless.
There may have been little to write home about in the first half but with little over 60 seconds on the clock in the second, Cardiff opened the scoring.
A trademark long throw in from Vaulks ended up at the feet of Bluebird’s skipper Sean Morrison. His effort was saved well by Sam Johnstone but fell kindly to Callum Paterson to poke home from close range.
The goal brought the game to life and the visitors should have drawn level moments later. Livermore’s cutback put the ball on a plate for Felipe Krovinovic but with the goal at his mercy, the Croatian fired over.
Slavan Bilic decided that a change was required to get his side back into the game and opted to bring on Charlie Austin for Kyle Edwards just shy of the hour mark.
Two minutes later the Englishman found himself on the scoresheet via the penalty spot. A great piece of skill from Krovinovic saw the midfielder flick the ball over the head of Jazz Richards before being brought down by the Cardiff man.
Austin stepped up and sent Alex Smithies the wrong way to bring the pre-match league leaders level.
Neil Harris looked for a super sub of his own, bringing on fan favourite Lee Tomlin for the disappointing Glatzel as Cardiff looked for a winner to keep their playoff push on track.
It was a moment of magic from Tomlin to put the Bluebirds back ahead. He was brought down on the edge of the area before stepping up to fire an unstoppable free kick into the top left hand corner, leaving Johnstone with no chance.
Tomlin could have grabbed himself a second five minutes later as he found some space inside the area but his near post effort flew just wide of the upright.
It was a miss which almost proved crucial as deep into stoppage time former Cardiff man Kenneth Zohore had a great chance to nick a point for the visitors but Cardiff keeper Alex Smithies was equal to it, producing a stunning one handed save to give his side the three points.
The result sees the hosts move up to twelfth in the league, five points adrift of the playoffs. West Brom meanwhile are now without a win in seven league games and fall a place to second, with Nottingham Forest hot on their heels, just two points adrift in third.