Ebou Adams (left) took his season's tally to six Championship goals with his header
Derby County claimed a crucial win in their battle for Championship survival as they all but ended West Bromwich Albion's faint play-off hopes with victory at The Hawthorns.
Ebou Adams' near-post header and Jerry Yates' close-range strike put the Rams in command before Adam Armstrong's cool second-half strike gave the Baggies hope.
However, Nathaniel Mendez-Laing raced clear late on to squeeze in Derby's third from a tight angle and end Derby's four-game winless run.
The victory keeps Derby outside the bottom three on goal difference on a day when several of their relegation rivals also won, while Albion drop to 10th, six points off the top six with two games to go.
The Baggies require a mathematical miracle to make the top six, needing to win both of their remaining games, while hoping Coventry lose both of theirs and that results involving three other sides go their way too.
This was their fifth defeat in six games, a rotten run that has virtually ensured Tony Mowbray's side will still be playing second-tier football next season.
They were twice caught cold from corners in the opening half hour as Adams nodded home Marcus Harness' delivery and Yates turned home inside the six-yard box after a ricochet fell kindly.
West Brom responded well as Isaac Price's 25-yard curler shaved the post and Tom Fellows' point-blank volley was superbly saved by Rams goalkeeper Josh Vickers.
They pulled one back with 20 minutes to go as Armstrong raced clear to nutmeg Vickers but Mendez-Laing produced an even smarter finish to seal the win, lobbing Albion keeper Josh Griffiths and trapping the dropping ball before tucking home.
With many of the sides battling the drop also picking up points, it was a vital victory for John Eustace's Derby, who face a huge six-pointer next Saturday at Hull City, who are one place and two points better off than the Rams.
West Brom manager Tony Mowbray told BBC Radio WM:
"Obviously, it's a tough period for us. I haven't seen anything since I've been here like the goals we conceded today from the set-plays.
"It's so unlike us. Two set-play goals from a hard-working, honest team. I thought we lacked courage today, didn't play enough forward es, weren't brave enough on the ball.
"When your team's in situations like we're in, I've had a difficult few weeks, people have to stand up and we can't do the job, play forward es, run forward and be brave and we lacked a bit of that today."
Derby County boss John Eustace told BBC Radio Derby:
"It was an amazing performance, I thought the lads were outstanding - we limited a really good footballing team to next to nothing really.
"We've conceded some sloppy goals this season and the one we conceded was sloppy again but we have to (Sondre) Langas is playing with a knee injury and will need some big surgery in the summer so just to get him in the team at the moment is great.
"We want to make this club special again and make the fans know whoever puts on the shirt will sweat blood for this club - as long as we keep fighting we'll give ourselves the best chance we can."
