Chelsea's second visit to Loftus Road was marked by controversy with Juan Mata converting a disputed penalty to send Andre Villas-Boas's side into the FA Cup fifth round at the expense of QPR.
The teams' first meeting in October ended with Chelsea reduced to nine men and skipper John Terry charged with racially abusing QPR defender Anton Ferdinand.
Both players started the game with Terry included in the starting line-up four days before the case arising from the previous game is due to be heard by West London Magistrates Court.
This time, however, the post-match inquest was centred on Chelsea striker Daniel Sturridge who went down theatrically under a challenge from Clint Hill, convincing referee Mike Dean to award the decisive spot-kick.
The much anticipated tie proved to be an anti-climax from a footballing point of view, but both clubs will be relieved that nothing added to the tensions arising from the fall-out from the first game.
The build-up to the game had been highly-charged and intensified when it emerged the Metropolitan police were investigating malicious communication sent to Ferdinand, believed to be a shotgun cartridge.
Additional police cover had already been planned for the game and the two clubs had issued a joint statement in the build-up to the game pleading for calm from both sets of fans.
That did little to silence the boos and chants, directed largely at Terry by the home supporters, but the potential confrontation between Ferdinand and Terry before the match was removed when the FA agreed to a request from both clubs to abandon the usual pre-match handshake.
The match itself was anything but explosive during the opening 45 minutes.
Chelsea's previous visit had provided no end of controversy, long before Terry's alleged abuse of Ferdinand.
Then, Villas-Boas' side were guilty of losing their discipline, collecting two red cards before the interval, yet still came close to claiming a point in a narrow 1-0 defeat.
This time, however, the visitors quickly assumed control of the game without converting their territorial advantage into clear chances on goal.
Fernando Torres was again employed as his side's main striker and while the Spain international did well to set up a Raul Meireles volley that flew wide, he was unable to carve out an opportunity to test Rangers keeper Paddy Kenny.
The home side worked hard to contain Villas-Boas' team but were ineffective as an attacking force and it took them 36 minutes to direct a shot at Petr Cech's goal, a long range shot from Shaun Wright-Phillips that was well off target.
The game finally came to life in the second period with Mata testing Kenny just five minutes after the restart before Torres again did well inside the area to set up Sturridge who shot wastefully over.
Mark Hughes's side responded positively with Wright-Phillips breaking into the Chelsea box before firing an angled shot that Cech could only parry away.
Rangers paid a price for a rare moment of adventure, however, as the visitors broke immediately with a sweeping move that led to the controversial penalty.
Ramires led the attack, moving the ball out to Mata who floated a cross towards Sturridge who fell theatrically to the ground after the slightest of collisions with Hill.
The two players had clashed moments earlier when Sturridge went down under a challenge from the left back only for referee Mike Dean to wave away the Chelsea man's appeal for a penalty.
This time the match official decided in favour of the striker despite QPR's complaints Sturridge had dived and Mata converted confidently from the spot.
Chelsea were forced to reorganise when Ramires fell awkwardly and was stretchered off with his leg in a splint after receiving treatment for several minutes but they adapted quickly and retained control during the closing quarter of an hour.