The Juventus goalkeeper was on form in the shootout to keep out efforts from Forlan, Caceres and Gargano as the Azzurri won on penalties to finish in third place.
Davide Astori slotted home Italy's opener after an unfortunate deflection off the goalkeeper, before Edinson Cavani's slotted finish restored parity.
Two brilliant free kicks, from Alessandro Diamanti and Cavani late in the second half, added to the score, before an entertaining match was settled on penalties after a competitive extra-time period.
In the shootout, Diego Forlan saw his effort saved by Gianluigi Buffon, before misses from Walter Gargano and Martin Caceres saw Cesare Prandelli's men claim third.
Despite the extra day of recovery, Uruguay was forced to defend early in match, with Giorgio Chiellini glancing a header narrowly wide after a good delivery from Alessandro Diamanti.
Minutes later, Daniele de Rossi produced a fine pass to set De Sciglio on the flank, with the latter supplying a dangerous low ball into the box, allowing Antonio Candreva to fire a tame shot at Fernando Musera in the best of the opening exchanges.
Italy continued to pose a few problems for La Celeste, and was deservedly ahead halfway through the first period, though who would actually be credited with the goal provided a bit of controversy and a moment of history.
Diamanti's fine set piece from the right slammed against the crossbar, before taking a cruel blow off the back of bamboozled goalkeeper Muslera and on the line before Astori made sure tapping the ball into the net and hand the Azzurri the lead. After the goal, FIFA sanctioned use of goal-line technology for the first ever time to determine the goalscorer.
Oscar Tabarez's side rallied following that setback. First, Luis Suarez fired a testing effort at Buffon which the Italy keeper smartly tipped over the bar, before Cavani's header into the net from Forlan's free kick was ruled out for offside.
Uruguay grew in confidence in the second half, and soon equalized. Walter Gargano led the surge through the midfield before picking out Cavani with a fabulous pass, slipping the ball behind the defenders, before the Napoli forward coolly curled a low finish past Buffon.
The South Americans continued in the ascendancy, and were somehow kept out by a supreme double save from Buffon. Forlan capitalized on a neat pass to launch a stinging effort at the Italy captain, who produced a world-class stop to keep Italy in the game.
The Azzurri were soon to be ahead after Diamanti made no mistake from a free kick on 73 minutes which nestled into the top corner. Moments later, it was 2-2 with Cavani repeating the trick with a sumptuous free kick from 30 yards which beat Buffon as the game progressed towards extra time.
The additional 30 minute period failed to separate the teams once more, but Montolivo was sent off for a second bookable offense following a clumsy trip on Suarez, though Uruguay failed to capitalize on the advantage as the match was eventually settled on penalties.
Emanuele Giaccherini capitalized on three misses from Uruguay to slot home Italy's third in the shootout, and claim victory in what has been a positive tournament for Italy ahead of next year's World Cup.