Giampaolo Pazzini turned out to be the hero for Sampdoria as he scored in extra-time and fired in the winning penalty.
Giampaolo Pazzini turned out to Samp's savior in this Round of 16 tie as he scored from the spot in extra-time to make it 2-2 and then rolled home what turned out to be the winning penalty in the shoot-out as Mauricio Isla failed to convert his.
Federico Macheda scored his first goal for the hosts in the first-half but it was canceled out by Mauricio Isla in the 90th minute.
German Denis then gave Udinese an early lead in extra-time and despite the hosts going down to ten men after Daniele Dessena was sent off, Pazzini successfully converted his spot-kick to take a topsy-turvy match into penalties.
Sampdoria were by far the better side in the opening quarter of an hour as they created two good chances. The first one was crafted as early as the fifth minute when Daniele Mannini whipped in a cross for Pazzini but the Italy international striker couldn't direct his header into the net.
Ten minutes later the hosts once again conjured up a chance when Mannini put in a low cross from the right but neither Pazzini nor Macheda could reach it.
Udinese were put firmly on the backfoot and struggled to launch an attack of their own. The Bianconeri were put under danger again midway through the first-half when once more Mannini delivered a wonderful cross from the right, but Pazzini's volley went over the crossbar.
Moments later Macheda tried his luck with a shot from outside the Udinese penalty area and before long the 19-year-old Italian on loan from Manchester United swooped in on a Stefano Guberti cross and forced goalkeeper Emanuele Belardi into making a save.
Macheda eventually found the target on 32 minutes when his shot deceived Belardi, slipping under the crossbar, giving Samp a 1-0 lead at the break.
Udinese coach Francesco Guidolin brought on Alexis Sanchez for Antonio Di Natale in order to shake things up a bit in the attacking department and ten minutes later the 22-year-old created a chance for Almen Abdi.
Samp continued to look for a second goal as Angelo Palombo went close and so did Pazzini in the closing stages, but in the 90th minute Isla equalised for Udinese to take the game into extra-time.
Two minutes into the extra frame the Zebrette went ahead for the first time through Denis as the Argentine turned in a corner. Mannini and Guberti then forced Belardi into making saves before Sampdoria went down to ten men as midfielder Dessena was sent off.
However, Pazzini successfully converted a 109th minute penalty that was won by Andrea Poli to make it 2-2 and take the match into penalties, where Pazzini struck his side's fifth before Isla failed to covert his spot kick, meaning that Sampdoria go through to the last-eight.
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