Trailing 11-10, Ireland won back possession from a knock on and Paddy Wallace attacked on the right before they worked it back into the middle, through a couple of phases, and Eoin Reddan's precise pass set up O'Gara for the decisive drop goal from outside the 22.

Ireland, with Denis Leamy in the sin-bin, used all their experience to dig out a result that hung in the balance right until the final seconds.

Luciano Orquera's long range attempt at a drop goal was never on target, leaving the Irish to reflect on a hard-fought victory.

Declan Kidney's men had their moments in attack and should have been out of sight by the time McLean crossed in the left corner. But they failed to convert a number of try-scoring chances, leaving Brian O'Driscoll's score in the 44th minute as their sole reward.

O'Driscoll cut past the two Italian props to score to the left of the posts, nudging his side into the lead for the first time. Jonathan Sexton added the conversion for a 10-6 advantage.

With the final kick of a cagey opening half, Mirco Bergamasco's second penalty success had moved the Azzurri into a 6-3 lead.

However, Ireland carried much more of a try-scoring threat and had things clicked into place for them, the winning margin would have been far more comfortable. O'Driscoll, Gordon D'Arcy and Keith Earls were left ruing missed scoring chances.

These sides are due to meet again at the Rugby World Cup on October 2, and they will have learnt a fair bit about each other in this scrappy encounter.

Ireland were missing 12 players through injury, among them Jamie Heaslip and Tommy Bowe, yet still fielded a side averaging 35 caps per player.

Winger Fergus McFadden was the only debutant for the Irish, but prop Mike Ross and number 8 Sean O'Brien were also making their full Championship debutants.

After Bergamasco kicked Italy ahead, unforced errors hampered Ireland's attempts to make inroads with O'Brien spilling the ball in contact and O'Driscoll firing away a loose pass.

They exploded into life in the 20th minute with Earls and full-back Luke Fitzgerald using quick ball to release Sexton, but the Leinster out-half was caught five metres out.

Full-back McLean executed a try-saving tackle on O'Driscoll as Ireland renewed their assault. Italy were buckling but were saved on two overlaps when first Earls juggled with the ball, conceding precious moments for the Azzurri to react, and then D'Arcy dropped a pass.

The one-way traffic continued but it took until the 28th minute for Ireland to level the game at 3-3 with a penalty from Sexton.

Bergamasco missed a long but straight three points amid a promising period from Italy, who saw hard-running centre Alberto Sgarbi make good ground.

Pressure from their front row resulted in Ireland being penalised at a scrum and it was now the visitors' turn to weather the storm.

Kris Burton failed with a drop goal attempt - the Azzurri seemed to be moving nicely through the gears - before the first half was closed out with Bergamasco's second successful penalty.

A powerful run from flanker Leamy signalled Ireland's intent for the second half and just four minutes in, they raced ahead.

Earls carried the ball over the gainline and, once Sexton had returned from a blind alley, play was swept out to the left where O'Driscoll found a gap and scampered over from close range.

Sexton nailed a tricky conversion and then placed Ireland deep in Azzurri territory with a towering touchfinder.

Earls and O'Driscoll made inroads before the Ireland skipper's pass was just too high for McFadden. Had it been accurate, the Kildare man was almost certainly over for a debut try.

Italy were continuing to resist stubbornly and kept in the game by Irish errors at key moments as much as their own heroics with D'Arcy spilling the ball two metres out.

For all Ireland's hard graft and attacking flair, they were still only 10-6 ahead. When Italy's pack set off on a rolling maul that took them 10 metres short of the line, the visitors' position looked precarious.

Nick Mallett's men were in their element as a series of scrum followed, before centre Gonzalo Canale was brought down with a shuddering hit.

Leamy was sin-binned for killing the ball and the drama continued when Italy used their powerful pack to batter the whitewash.

Inspirational number 8 and captain Sergio Parisse almost found a way through but they were not to be denied in the 75th minute when slick handling sent McLean in at the left corner. Bergamasco's conversion attempt went narrowly wide.

However, Ireland used all their experience to patiently work themselves into a scoring situation and O'Gara coolly landed the drop goal to snatch victory from the jaws of defeat.