A second-half strike from Alassane N'Diaye condemned West Brom to their first defeat of the season.
High-flying West Brom brought down to earth
West Brom's unbeaten start to the Championship season finally came to an end after they were beaten 1-0 at home by Crystal Palace.
Young midfielder Alassane N'Diaye scored the only goal of the game just after the hour mark to secure a surprise victory for Neil Warnock's side.
The Baggies, whose last league game was a 5-0 hammering of fellow high-flyers Middlesbrough, came close to scoring through Luke Moore and Graham Dorrans but ultimately could not find the back of the net.
The visitors were clearly not daunted by the prospect of facing-off against the in-form Baggies as Neil Danns crashed a 25-yard effort just over with barely two minutes gone.
Danns went close again from a similar distance five minutes later before having his header from a Danny Butterfield cross saved by Scott Carson as Palace dominated the early stages.
Chances
There was over 20 minutes gone when West Brom created their first noteworthy opportunity of the afternoon, Gonzalo Jara firing straight at Julian Speroni from the edge of the penalty area.
The lively Victor Moses, looking for a first goal of the season, twice tried his luck from long distance, but on both occasions missed the target.
Speroni had to be alert after 39 minutes to ensure Dorrans' inswinging corner did not find a way past him, while Darren Ambrose shot wide from 20 yards at the other end on the stroke of half-time.
Palace continued to pile on the pressure after the break, Danns drilling a right-footed shot wide from fully 30 yards, with Dorrans also going close for Albion inside the opening exchanges of the second period.
Just before the hour mark, Speroni produced a fantastic save to keep out Moore's close-range effort after the former Aston Villa trainee had raced on to Gianni Zuiverloon's centre.
Changes
Zuiverloon and Moore were then hauled off and replaced by Reuben Reid and Simon Cox respectively as Albion boss Roberto Di Matteo attempted to add a more potent attacking threat to his side.
However, it was Palace who deservedly broke the deadlock after 63 minutes of play.
Shelton Martis should have dealt with a punted long ball but hesitated and N'Diaye pounced to coolly slot past Carson for his first senior career goal.
Jonas Olsson could have levelled for Albion four minutes later when he met another threatening Dorrans corner, only to see his near-post header flash over the bar.
Roman Bednar headed wide from six yards and Dorrans shot over from 18 yards as Albion came forward in search of an equaliser.
Joe Mattock was denied by Speroni from 20 yards as Palace found themselves under heavy pressure half late on, but held on for the three points.
