Charlie Austin’s late winner against his former club gave QPR a dramatic victory over promotion rivals West Bromwich Albion.
Austin, on as a substitute, got in front of Taylor Gardner-Hickman to head Chris Willock’s cross into the far corner of the net.
It took Rangers above Albion to fourth in the Championship table.
West Brom, now without a win in four matches, were the better side in the first half but Matt Phillips missed their best chance.
Karlam Grant went past Rob Dickie on the left and crossed low towards the former QPR winger.
But Phillips, under pressure from ex-Albion midfielder Sam Field, was unable to get a decisive touch, glancing wide of the target from close range.
Callum Robinson sent a shot wide as the Baggies continued to press, and Grant saw an effort saved by veteran keeper David Marshall, who made his R’s debut following a move from Derby County.
At the other end, Stefan Johansen’s free-kick was gathered by keeper David Button, who saved a more threatening strike from the Norwegian shortly before the interval.
The home side wore a special-edition kit – a shirt with light and dark blue halves to mark 140 years since the formation of Christchurch Rangers, who later merged with another local club, St Jude’s Institute, to form Queens Park Rangers.
Having struggled in the first half, QPR were much better after the restart and had a goal disallowed when Andre Gray blasted in after being put through by Willock but fouled Matt Clarke in the build-up.
There was another scare for Albion when Rob Dickie’s cross from the right was turned over the bar by Lyndon Dykes.
West Brom, having previously been comfortable, were now under serious pressure and Dykes was just unable to get Johansen’s pass under control, enabling Button to intercept.
Button, playing in the absence of the suspended Sam Johnstone, was then called into action again, this time to push away Willock’s powerful shot.
With his team struggling, West Brom boss Valérien Ismaël sent on £7m signing Daryl Dike for his debut.
The young American striker made an immediate impact, finding space on the right and setting up Jake Livermore, who shot over, and finding Grant, whose deflected cross almost caught out Marshall at the near post.
Dike certainly made a mark on Yoann Barbet, bundling him head-first into the advertising hoarding.
Barbet needed several minutes of treatment but had his head strapped, changed his bloodstained shorts and played on.
And shortly before Austin’s decisive goal, referee Simon Hooper waved play on when Albion appealed for a penalty after Conor Townsend went down under a challenge from Johansen.
QPR: Marshall; Dickie, Dunne, Barbet; Adomah, Field, Johansen, Wallace; Willock (Ball 90); Gray (Austin 64), Dykes.
Subs not used: Walsh, Amos, Thomas, Dozzell, Odubajo.