Karlan Grant had not scored for Albion since the Baggies' second game of the season - the 3-2 home win over LutonKarlan Grant hit his second match-winner of the season for West Bromwich Albion to send the Baggies back to the top of the Championship table.
Last season's £15m signing from Huddersfield Town hit the winning goal in the 88th minute in a game turned on its head late on when Grant's on-target effort triggered a very costly error from QPR keeper Seny Dieng.
On-loan Watford striker Andre Gray had fired Rangers ahead after just 45 seconds - and the Hoops still held that lead with 15 minutes left.
But, when Grant unleashed a speculative low left-foot shot on the angle from 15 yards, Dieng got down low to make the save only to then clumsily flap the loose ball into the net with his spare hand to register a sickening own goal.
And, with just two minutes left, Grant beat Dieng again from a similar angle, this time with a low finish into the far bottom corner, to lift the Baggies from fourth back to top spot, ahead of Saturday's fixtures.
Wolverhampton-born Andre Gray's goal inside the first 45 seconds at the Birmingham Road End stunned the Baggies fansLess than a minute had elapsed when Albion went behind to a swift QPR counter-attack.
Grady Diangana was dispossessed on the edge of the Rangers box and the visitors broke upfield where Moses Odubajo slipped in Gray - and the former Luton, Brentford and Burnley striker slid the ball under keeper Sam Johnstone from a tight angle.
Albion were quickly close to levelling it up but Diangana fired just wide from 20 yards, then did the same again when he could have done better, opting to shoot when he had other options.
Rangers keeper Dieng also had to be at his most alert to parry Adam Reach's powerful header.
But, after QPR had seemingly soaked up whatever Albion had got to throw at them, Dieng had only himself to blame for the hosts' leveller.
And, having been involved in the equaliser, Grant then hit the winner.
He only managed to score once in the Premier League last season, but this was his second winning goal at The Hawthorns in little over a month after netting Albion's third in the 3-2 win over Luton in August.
Line-ups
West Brom
Formation 3-4-3
1Johnstone
6Ajayi5Bartley3Townsend
2Furlong8Livermore27Mowatt20Reach
11Diangana10Phillips18Grant
1Johnstone6Ajayi5Bartley3Townsend2Furlong8Livermore27Mowatt20Reach11DianganaSubstituted forHugillat 55'minutesBooked at 90mins10PhillipsSubstituted forRobinsonat 54'minutes18GrantSubstituted forBryanat 90'minutesSubstitutes
7Robinson14Molumby17Hugill21Kipré22Bryan23Snodgrass25ButtonQPR
Formation 3-4-2-1
1Dieng
4Dickie5de Wijs20Dunne
22Odubajo12Ball7Johansen6Barbet
10Chair21Willock
19Gray
1Dieng4Dickie5de WijsSubstituted forKakayat 77'minutesBooked at 86mins20Dunne22Odubajo12Ball7JohansenSubstituted forDozzellat 79'minutes6Barbet10Chair21WillockSubstituted forDykesat 66'minutes19GraySubstitutes
2Kakay9Dykes11Austin14Thomas17Dozzell32Walsh37AdomahLive Text
Match ends, West Bromwich Albion 2, Queens Park Rangers 1.
Second Half ends, West Bromwich Albion 2, Queens Park Rangers 1.
Corner, Queens Park Rangers. Conceded by Adam Reach.
Foul by Kean Bryan (West Bromwich Albion).
Andre Gray (Queens Park Rangers) wins a free kick in the attacking half.
Jordan Hugill (West Bromwich Albion) is shown the yellow card for a bad foul.
Foul by Jordan Hugill (West Bromwich Albion).
Robert Dickie (Queens Park Rangers) wins a free kick in the defensive half.
Corner, Queens Park Rangers. Conceded by Kyle Bartley.
Substitution, West Bromwich Albion. Kean Bryan replaces Karlan Grant because of an injury.
Foul by Jordan Hugill (West Bromwich Albion).
Jimmy Dunne (Queens Park Rangers) wins a free kick in the defensive half.
Goal! West Bromwich Albion 2, Queens Park Rangers 1. Karlan Grant (West Bromwich Albion) left footed shot from the centre of the box to the bottom right corner. Assisted by Callum Robinson.
Attempt saved. Darnell Furlong (West Bromwich Albion) right footed shot from outside the box is saved in the centre of the goal.
Attempt saved. Kyle Bartley (West Bromwich Albion) header from the centre of the box is saved in the centre of the goal. Assisted by Darnell Furlong with a cross.
Attempt blocked. Karlan Grant (West Bromwich Albion) right footed shot from outside the box is blocked.
Corner, West Bromwich Albion. Conceded by Yoann Barbet.
Osman Kakay (Queens Park Rangers) is shown the yellow card for a bad foul.
Karlan Grant (West Bromwich Albion) wins a free kick on the left wing.
Foul by Osman Kakay (Queens Park Rangers).
