Pool C/ Scotland 18 Italy 16:This was a match Scotland would have lost a couple of years ago.

They may not have Wales's flair, England's capacity to strangle opponents or Ireland's pedigree, but unlike the other three home unions in this tournament, they have played close to the maximum of their potential and in Frank Hadden they have a coach who squeezes every last drop out of his charges.

The quarter-final decider was never going to be gung-ho like the Wales-Fiji match that preceded it, even before the rain set in an hour before kick-off. There was something archetypally Six Nations about it, a raw encounter with two sets of snarling forwards determined to bestow the role of extras on their three-quarters. Hadden's strategy of taking on the Italians at their own game, neutralising a perceived Azzurri strength up front, and using the unerring boot of Chris Paterson to punish every discretion, paid off.

Scotland's strategy was to make the fewer mistakes, which meant Dan Parks kicking the ball, whether long or high, and rarely passing it along his back line. In contrast, his opposite number, Ramiro Pez, endured a dreadful evening, lacking even a measure of control.

Italy missed their injured captain, Marco Bortolami, and lacked leadership at crucial times. The veteran scrumhalf Alessandro Troncon took over the armband, but as a player his best years are behind him. After the match clock had reached 80 minutes, Italy were in Scotland's half, needing to take the ball around the fringes and make the few yards needed to take them within David Bortolussi's penalty range but Troncon, after a few drives, kicked the ball limply and Parks caught it to take Scotland into the knock-out stage.

Italy were the most indisciplined team out of the 20 finalists and should have had more than Mauro Bergamasco sinbinned on Saturday. Conceding penalties within the range of Paterson, who maintained his 100 per cent record with six penalties, amounted to a suicide note writ large.

Troncon himself was fortunate to get away with a high challenge off the ball on Parks who had earlier been tripped by Mirco Bergamasco. At least Italy had identified one of Scotland's main threats: Parks may not be an exciting outhalf but his functional approach was exactly what was demanded.

When Scotland's first scrum was twisted around in the opening minute, Italy's large support roared, but instead of being reset in the Azzurri's favour, Paterson lined up a penalty, the first of two in the opening five minutes. Italy surged back after Mauro Bergamasco saw yellow for obstruction after Troncon's slip had set up the Scots' only try opportunity of the night.

Troncon scored Italy's try after Rory Lamont had appeared to be impeded trying to catch a high kick while in the air and Bortolussi made it 10-6 with the first of his three penalties, but two more Paterson kicks gave Scotland the lead they were not to lose.

Paterson played down his contribution. "I know there will be times when I miss kicks, but I hope to keep those to a minimum. It was always going to be tight against Italy and playing [ for] territory to get penalties to kick was important. We had spent five months working towards this game . . . and we are delighted to win. We now move forward," he said.

Scotland got away with some scrappy work at the breakdown, but it was a triumph for Hadden whose decision to rest all his forwards against New Zealand the previous week was fully vindicated.

• Guardian Service

SCOTLAND: R. Lamont; S. Lamont, Webster, Dewey, Paterson; Parks, Blair; Kerr, Ford, E. Murray;Hines, Hamilton; White, Hogg, Taylor. Replacements: Southwell for R. Lamont (25), Henderson for Dewey (60), Cusiter for Blair (72),Smith for Kerr (65), MacLeod for Hamilton (72), Brown for Hogg (70). Not used: S. Lawson. Sin bin: Hines (55).

ITALY: Bortolussi; Robertson, Canale, M. Bergamasco, Masi; Pez, Troncon; Perugini, Festuccia, Castrogiovanni; Dellape, del Fava; Sole, M. Bergamasco, Parisse. Replacements: Galon for Masi (75), Lo Cicero for Perugini (49), Ongaro for Festuccia (54). Not used: Bernabo, Ghiraldini, Griffen, de Marigny. Sin bin: M. Bergamasco (9).

Referee: J Kaplan(South Africa).