QPR bowed out of the FA Cup at the fourth round stage after a slender 1-0 defeat against West London rivals Chelsea.
In the 50th competitive meeting between the two sides, this tight encounter was ultimately decided by a disputed penalty.
Juan Mata's cross eventually led to a coming together between Clint Hill and Daniel Sturridge, before the Chelsea man fell to the ground under minimal contact.
Referee Mr Dean pointed to the spot before Mata struck what proved to be the winner, tucking the ball into the bottom right-hand corner from 12 yards on 62 minutes.
Rangers made just one change the starting XI which brushed aside Wigan in the Barclays Premier League last weekend, with Tommy Smith replacing the injured DJ Campbell (hamstring).
Nedum Onuoha, meanwhile, was named on the bench, following the centre-back's switch from Manchester City in midweek.
Paddy Kenny was in goal for QPR, who lined up in a 4-4-2 formation.
Luke Young, Anton Ferdinand, Fitz Hall and Clint Hill made up Rangers' defence.
In midfield, skipper Joey Barton partnered Akos Buzsaky in the middle of the park, with Jamie Mackie and Shaun Wright-Phillips manning the flanks.
Smith joined Heidar Helguson in attack.
The opening stanza was one of very few opportunities of note - that in the midst of a rip-roaring atmosphere at Loftus Road.
Daniel Sturridge's wayward shot from distance was the only effort to note inside the first ten minutes.
The first real chance of the contest arrived on 12 minutes. Mata burst into the R's box before seeing his left-footed drive blocked away by Kenny.
QPR's opening opportunity arrived two minutes later, with Barton lashing an effort wide on the half-volley from the edge of the box.
The first half never really got going, in truth, with both sides refusing to give an inch.
The next opportunity didn't arrive until the 34rd minute - Raul Meireles seeing his blast from 25 yards go only inches past the upright.
Rangers broke through Smith just two minutes later, with the forward feeding Wright-Phillips before the former Blues ace blazed an effort well wide of the target from 25-yards out.
Chelsea went close five minutes before the break. Mata's clever back heel found Ramires on the right-hand side of the box, whose drive across the face of goal somehow flashed wide of the far post.
In a bid to freshen things up at the interval, Hughes introduced Federico Macheda in place of Helguson.
It was the visitors, however, who were first to go close.
Fernando Torres teased both Hill and Ferdinand down the right before teeing up Sturridge just inside the penalty area, whose thunderbolt shot whistled just over the bar.
The Blues were enjoying a large chunk of possession following the half-time break.
David Luiz soon fashioned another chance for Andre Villas-Boas' side, with his effort from distance bouncing wide of the left-hand post.
But the longer the second period wore on, the more Rangers could sense an opening.
That chance arrived on 60 minutes and, with a little more luck, could have led to the opening goal.
Wright-Phillips broke free of Ashley Cole in the box and, when the diminutive winger's subsequent low drive was only parried by Petr Cech, the ball just evaded the waiting Mackie on 12 yards, before Chelsea cleared their lines.
Controversy struck under a minute later when the Blues were awarded a penalty - a decision that was to prove crucial.
Mata's centre into the box led to a coming together between Hill and Sturridge, before the latter fell to the ground under minimal contact.
Referee Mr Dean deemed that to be an unfair challenge, duly pointing to the spot.
Mata - architect of the cross that led to the spot-kick - stepped up to take the resultant penalty and made no mistake, sending Kenny the wrong way by sliding the ball into the bottom right-hand corner.
Rangers huffed and puffed for an equaliser - something that looked increasingly unlikely until deep into seven minutes of time added on.
Young broke free of his marker down the right and, when his cross-come-shot was only spilled by Cech back into a crowed penalty area, Chelsea just managed to avert the danger.