MALAGA, Spain (Reuters) - Italy's Jannik Sinner saved matchpoints to upset Novak Djokovic 6-2 2-6 7-5 and help his country to draw level with Serbia in their Davis Cup semi-final on Saturday after Miomir Kecmanovic had put the 2010 champions ahead by beating Lorenzo Musetti 6-7(7) 6-2 6-1.
Italy are aiming to return to the final having last reached that stage a quarter of a century ago and the 1976 champions can succeed if they prevail in the deciding doubles contest at a packed Martin Carpena Arena.
Sinner was facing Djokovic for the third time in 11 days and the world number four, who beat the top-ranked Serbian early in the ATP Finals before losing to him in the title clash, made a quick start to ease through the opening set with two breaks of serve.
The 22-year-old, who had sparked Italy's comeback in their quarter-final against the Netherlands, took his foot off the gas in the next set to allow Djokovic back in but kept chipping away in the hope of sealing a second win over him in six meetings.
He saved three matchpoints while down 4-5 in the decider and then pulled off one of the most remarkable wins of his career to spark wild celebrations in the stands.
Defeat was a bitter blow for Djokovic, the winner of three of the four Grand Slams in a spectacular year, but the 36-year-old will be back for the decider later on Saturday to help Serbia try to reach a third final.
Serbia, who outclassed Britain in the last eight, last won the premier men's team competition in 2010.
Kecmanovic had earlier rallied from a set down to power past Musetti and leave Serbia one win away from their third final in the elite men's team competition and first since 2013.
Musetti made a slow start against the high-flying Kecmanovic and narrowly avoided going down a double break, before the world number 27 found his range to level the first set at 5-5 and come from behind again in the tiebreak to clinch it.
But Kecmanovic's level barely dropped following the setback, as the world number 55 breezed through the second set and broke twice in the third for a 4-0 lead, which was enough for the 24-year-old to see off Musetti who was battling a thigh issue.
The winner of the tie will face Australia in Sunday's final after Lleyton Hewitt's side beat Finland.