Dexter Blackstock rose from the bench to nod home a late winner, after Rangers had twice relinquished the lead to high-flying Preston North End.

In a topsy-turvy encounter, Heidar Helguson headed home an early opener, only for Chris Sedgwick to restore parity with a header of his own.

After an Agyemang header fell kindly for the Iceland international to bundle home his and Rangers' second, Referee Alan Wiley plunged the match into controversy by awarding a contentious penalty that Callum Davidson duly thundered home.

Not to be outdone, Rangers threw everything forward in search of a winner and more than deserved to snatch victory thanks to Blackstock's headed goal.

For the visit of the high-flying Lilywhites, Manager Paulo Sousa made a single change. The more attacking Hogan Ephraim came into the side to replace Mikele Leigertwood.

Elsewhere, Agyemang faced his former side, alongside Helguson, and Kaspars Gorkss once again kept Fitz Hall from returning to the starting line-up.

Preston handed a start to striker Jon Parkin after the 'Beast's' heroics against Birmingham City. On-loan duo Eddie Nolan and Ross Wallace retained their places in defence and midfield respectively.

Not two minutes in and the R's should've taken the lead, but for a phenomenal double save from visiting keeper Andy Lonergan.

Lee Cook - operating on the tip of the diamond - strode forward towards the Preston box and rifled a well hit shot that the Lilywhite keeper parried into the path of Agyemang. With the goal gaping, the Ghanaian miss-hit his shot, but Lonergan still needed to dive at full stretch to keep it out.

Rangers kept the pressure up and were duly rewarded in the 16th minute. After winning a throw deep in the Preston half, Cook's determined run and cross met the forehead of a stooping Helguson and he sent the ball beyond Lonergan to register his first Loftus Road goal.

Unfortunately for the R's, the next real chance fell to Preston, and they capitalised in emphatic style. Patient build-up play involving Wallace led to Paul McKenna crossing for Sedgwick to nod home the leveller.

The R's hit back, and Preston's Nolan came to the rescue to clear a beautiful Hogan Ephraim cross before an onrushing Helguson could connect.

The Icelander, however, was not to be denied, and when Martin Rowlands' pin-point corner was headed goalwards by Agyemang, Helguson was on hand to scramble the ball over the line and restore Rangers' lead.

Neat, flowing, wonderful football almost created a chance for Cook, but after Agyemang had slipped through a clever pass for the on-loan Fulham man, he could only watch agonisingly as the ball slipped just too far and was  cleared to safety.

Rangers were mesmerising, and Cook, Ephraim and Agyemang combined to almost tee-up Rowlands, but determined Preston defending kept the R's at bay for the time being.

And with that latest chance, referee Wiley blew a halt to proceedings.

Fortunately, Rangers, and in particular Cook, were in no mood to rest up for too long and instantly found their feet in the second period. Cook tested Lonergan with a volley from the edge of the area, seconds after the restart.

An even better chance fell for Agyemang, seconds later, as Helguson was freed down the left and clipped a pass over for his strike partner to let fly whilst airborne. His well-struck effort looked to be fizzing into the side of the net, only for the Preston keeper to dive full-length and palm it away to safety.

Preston were not lying down however, and Gavin Mahon had to be brave to dive in front of a venomous Davidson piledriver.

Preston continued to try and get back into the match and were given a massive helping hand by Wiley. As a Wallace free-kick was floated in, it found a way to Sean St Ledger via Parkin, and as the Irish defender tried to get a touch to send it goal-bound, out came Cerny to apparently push the ball away.

Wiley saw differently, however, and awarded Preston a penalty, which Davidson duly smashed down the middle to bring the Lilywhites, once again, level.

Reacting to the set-back, Sousa replaced Mahon with Leigertwood just past the hour.

And the substitute rose to the occasion, picking up the ball from Rowlands' inside pass before launching a rasping 25-yard drive that whistled wide of the left-hand upright.

Ephraim followed suit some minutes later after he was found lurking a similar distance from goal by Cook. Like Leigertwood, however, the shot went high and wide.

In a positive change, Sousa altered his formation, bringing on Hall and Blackstock and going 3-4-3.

And it almost paid dividends, as Hall played a cracking cross-field pass that found Cook on the left. He bamboozled his way past Nolan and chipped in a cross that bounced here, there and everywhere before Lonergan finally came and claimed it.

Sousa's gamble did pay off, however, as Rangers scored a third to lift the roof off Loftus Road. A foul on Cook gave Rowlands the chance to deliver a fine cross onto the head of the newly-introduced Blackstock, who rose majestically to guide home beyond the despairing dive of Lonergan.

The drama had not ended and Helguson was sniffing around for any chances to complete his hat-trick. A neat one-two with Blackstock nearly played him in, had it not been for a crucial tackle from Davidson.

A raucous noise greeted the final whistle as Rangers fans and players alike celebrated a fine win that saw the R's edge still further to the play-off places.

QPR: Cerny, Delaney (Hall 81), Stewart, Mahon (Leigertwood 62), Agyemang, Gorkss, Rowlands, Ramage (Blackstock 81), Cook, Ephraim, Helguson.

Subs: Ledesma, Di Carmine.

Scorers: Helguson (16), (34), Blackstock (85)

Bookings: Delaney (51)

Preston North End: Lonergan, Davidson, Mawene, Sedgwick (Whaley 90), Brown, Nicholson, St Ledger, McKenna, Wallace, Parkin, Nolan.

Subs: Neal, Hawley, Carter, Jones.

Scorers: Sedgwick (28)

Bookings: Sedgwick (45), Davidson (60)

Referee: Mr A Wiley

Attendance: 14,103