Italy head back to the BJK Cup final after 2-1 victory over Poland
Lucia Bronzetti put the Italians ahead with a 6-4, 7-6 singles win over Magda Linette but an imperious Swiatek worked her magic by beating Paolini 3-6, 6-4, 6-4 in singles and then was inches away from a comeback victory in a breathtaking doubles clash that went into the early hours of Tuesday.
Paolini, who has never beaten world number two Swiatek in their three previous attempts, including a 6-2, 6-1 defeat to the Polish juggernaut in the French Open final in June, started well and won the first set.
But in two evenly matched and very similar sets between the two highest ranked players in the tournament, Swiatek was clutch when it mattered the most and broke Paolini's serve in the 10th game to seal her victory in a thrilling 2 hours and 36 minutes, forcing the doubles decider in the southern Spanish city of Malaga.
It was a rare doubles performance for the five-time Grand Slam singles champion Swiatek, who played her first Billie Jean King Cup doubles match since 2019 on Saturday, when she and Kawa beat Czech Republic in the quarter-finals to advance to the final four for the first time.
And on Monday, the Polish pair put on a great fight against the Paris 2024 Olympic champions Errani and Paolini.
The Italians saved three set points in the first set, and rallied from a 5-1 deficit in set two, to finally close a 7-5, 7-5 win and advance to the final for a seventh time and second year in a row, having lost to Canada in 2023.
"It was tough, the intensity was insane, I was so tired but I had to give it all to my team and my country," Paolini said.
"I was sad after losing to Iga in singles but I went to the locker room and tried to be positive because I knew my teammates needed me."
In Wednesday's final, Italy will face either Britain or Slovakia, who play the other semis on Tuesday.