Derek McInnes struck in the ninth minute, driving home Lee Hughes' cross via a deflection, to give West Brom a 1-0 half-time lead against Crystal Palace.
West Brom, bidding to mark the 100th birthday of the Hawthorns with their second success in a week, wasted no time posing problems for the Palace defence.
Striker Hughes tested keeper Stuart Taylor after only two minutes with a well-struck shot after latching onto a fine pass from McInnes. Then, moments later, the impressive McInnes created another good opening for Hughes but this time the hitman's shot flashed across the face of the Palace goalmouth.
The roles were reversed in the ninth minute when Hughes opened up the Palace defence for McInnes to fire Albion into the lead. Hughes held off a challenge from defender Neil Ruddock before slipping the ball to McInnes who made no mistake with a blistering half-volley that deflected past the helpless Taylor.
Taylor saved again from Hughes in the 13th minute, and four minutes later McInnes' cross found Bob Taylor in space, but the former Bolton forward headed inches over the bar.
The Palace defence was struggling to cope with West Brom's incisive passing and full-back Des Lyttle got forward well after 23 minutes to drill a shot past the angle.
Palace rode out the Baggies' early storm and forced more of the possession as the half wore on. Palace were rarely afforded the space to attack, but former Middlesbrough defender Craig Harrison threaded a 38th-minute cross through to Clinton Morrison at the near post, but the striker could not direct his header.
In the last minute of the first-half a break through the middle by Bob Taylor almost set Hughes away, but he was stopped in his tracks by a marginal offside decision.