Djokovic beat former US Open champion Marin Cilic in the singles, levelling the semi-final tie after Croatia’s Borna Gojo won against Dusan Lajovic.
Nikola Mektic and Mate Pavic, the world number ones, put Croatia into the final with a 7-5 6-1 win in Madrid.
With the expertise of Mektic and Pavic proving crucial against the two Serb singles players, Djokovic said it illustrated the need for his nation to find a strong doubles pairing if they are to win the Davis Cup for a second time.
“We definitely need to improve our doubles part of the team.
We need to have a doubles team that is constantly playing together,” said Djokovic, who was instrumental in Serbia’s 2010 win.
“Otherwise it’s going to be a Mount Everest for us to climb every time we play like this.
Croatia won the first singles rubber when world number 279 Gojo fought back to win 4-6 6-3 6-2 against Lajovic, stretching his 100% record to three victories in a dream Davis Cup Finals for the 23-year-old.
Djokovic levelled the best-of-three tie by earning his 19th consecutive Davis Cup singles victory, fighting off eight break points against Cilic before winning 6-4 6-2.
That teed up a intriguing doubles match which featured the world’s best pairing and its leading singles player.
Mektic and Pavic, who won the Wimbledon and Olympic titles in a dominant 2021 season, had won all three of their Finals matches in straight sets and again showed their quality to do the same against the Serbs.
Davis Cup: Novak Djokovic and Serbia lose to Croatia in Madrid