Croatia dumped out much-fancied Italy in the Davis Cup quarter-finals on Monday as Olympic men's doubles champions Nikola Mektic and Mate Pavic brushed aside Jannik Sinner and Fabio Fognini in a deciding match.
The Italians were one of the favourites for the title but paid for Lorenzo Sonego's shock defeat by world number 279 Borna Gojo in the first singles rubber in Turin.
Singles world number 10 Sinner forced a deciding doubles with a dramatic victory over Marin Cilic, but he could not complete the job against the top two ranked doubles players as Mektic and Pavic won 6-3, 6-4 to silence the home crowd.
Croatia will next face either Novak Djokovic's Serbia or Kazakhstan in the semi-finals in Madrid.
"Honestly, it feels incredible. I don't think anyone expected us to get this far and it feels amazing to be going to Madrid," said Mektic.
Croatia are bidding for a third Davis Cup title and second in three stagings of the event after lifting the trophy in 2018.
Last year's edition was postponed due to the Covid-19 pandemic.
This win confirms their place at next year's Davis Cup Finals, with the four semi-finalists guaranteed qualification.
"It was very tight but my players fought so well. I'm so happy," said Croatian captain Vedran Martic.
Mektic and Pavic were the stronger pair throughout the doubles, with Fognini's serve often targeted.
They needed six set points to take the opener despite dominating, but wrapped up victory on their first match point in the second set as Pavic fired down an ace.
Earlier, rising star Sinner battled back from a set and a break down to beat Cilic and force the doubles rubber.
Italy were facing a quick exit in Turin when former US Open champion Cilic served for the match when leading 5-4 in the second set.
But Sinner fought back from the brink, breaking to love before taking a tie-break and going on to win 3-6, 7-6 (7/4), 6-3.
Gojo beat Sonego 7-6 (7/2), 2-6, 6-2 to give Croatia the first point.
The Croatian overcame a hesitant start, with the 23-year-old trailing the 27th-ranked Sonego 4-1 in northern Italy, before coming back from 5-3 down to take the first set in a tie-break.
Sonego, 26, powered back in the second set but dropped serve early in the final set at 2-1, with over 30 unforced errors allowing Gojo to win in 2 hours and 20 minutes.
In Turin, Italy
Croatia 2 Italy 1
Borna Gojo (CRO) bt Lorenzo Sonego (ITA) 7-6 (7/2), 2-6, 6-2
Jannik Sinner (ITA) bt Marin Cilic (CRO) 3-6, 7-6 (7/4), 6-3
Nikola Mektic/Mate Pavic (CRO) bt Fabio Fognini/Jannik Sinner (ITA) 6-3, 6-4