Sara Errani swept past compatriot, doubles partner and best friend Roberta Vinci to become the first Italian woman in the Open era to make the US Open semi-finals on Wednesday.
Errani, the 10th seed who was the French Open runner-up to Maria Sharapova this year, defeated the 20th-seeded Vinci 6-2, 6-4 and goes on to face either three-time champion Serena Williams or Ana Ivanovic for a place in the final.
The 25-year-old Errani was playing in her third Grand Slam quarter-final of the year while Vinci, four years older, was making her debut in a last-eight at a major at the 32nd time of asking.
The pair have won seven doubles titles in 2012, a haul which includes the French Open, but it was Errani's greater big-match experience which proved decisive on Wednesday.
"It's always hard to play against a friend and it was strange seeing her on the other side of the net," said Errani, who already has four tour singles titles to her name this year.
"I am happy to get to the final. Can I win the title? I will tell you in three or four days."
Errani broke in the first and seventh games of the first set, taking the opener on a fourth set point with Vinci undone by 21 unforced errors.
Only a few hundred fans roused themselves into Louis Armstrong Stadium to witness the first time that two Italian women had made the last eight of a major.
They then saw Errani take a crucial break, the fifth of the set, to lead 5-4 in the second set and wrap up the tie after 72 minutes when Vinci netted a service return, her 37th and final error of the match.