Juan Mata's hotly-disputed penalty helped Chelsea secure a 1-0 victory in a tempestuous FA Cup fourth-round tie at west London rivals Queens Park Rangers.

A match that for an hour was completely devoid of action suddenly sprang to life when Clint Hill was harshly adjudged to have bundled over Daniel Sturridge and Mata stepped up to score the only goal of the game from the spot.

Both sets of supporters cranked up the decibel level before kick-off but had little to cheer in a disappointing first half that saw only one shot on target.

That came after Mata, playing more centrally in the absence of Frank Lampard, pounced on a Luke Young slip in the 12th minute and unleashed a 15-yard drive too close to Paddy Kenny. Otherwise, the final ball from both sides was sadly lacking, meaning a succession of speculative efforts that were well off target.

A fixture that had seen Chelsea reduced to nine men in October was a more controlled affair and it was almost half an hour before Mike Dean brandished the first yellow card for a Shaun Wright-Phillips foul on Raul Meireles.

Ramires should have done better with great cutback opportunity after being released by a wonderful Mata backheel, but neither side deserved to be ahead at half-time.

QPR threw on Federico Macheda for Heidar Helguson at the restart but it was Chelsea who flew out of the blocks, with Fitz Hall booked for handball before Sturridge lashed over after great work from Fernando Torres.

Mata converts
But the game really exploded into life on the hour mark. Petr Cech parried a Wright-Phillips cross just too far in front of the outstretched foot of Jamie Mackie and Chelsea surged down the other end and won a penalty.

QPR were furious at the award but Mata shrugged off the jeers to score, the midfielder celebrating with most of his team-mates in front of the visiting fans.

Ashley Cole was carded for fouling Wright-Phillips before Chelsea lost Ramires to a serious-looking injury. The midfielder appeared to twist his ankle blocking a shot and, after several minutes' treatment, was carried off on a stretcher to be replaced by Oriol Romeu.

QPR had already thrown on Rob Hulse, who was denied a penalty in the closing minutes. And there was a flashpoint deep into stoppage time when Romeu was booked for diving in on Hulse, with Young almost snatching a draw when his 20-yard drive was parried by Cech.