Borini hails Sunderland support at Old Trafford
Nine thousand supporters saw their side book a trip to Wembley after a dramatic penalty shootout victory against Manchester United.
"It was unbelievable support. A piece of my heart will stay with Sunderland - the club, the supporters, the players," he told the club's official website.
In a crazy conclusion, Phil Bardsley's 119th-minute shot was spilled into the net by David de Gea, looking to have handed Sunderland their place in the final.
But their dreams seemed dashed seconds later as Javier Hernandez struck to ensure a penalty shootout, sending Old Trafford into delirum.
"I've never seen anything like it - that's why we love football. Vito [Mannone] made unbelievable saves and credit to him because he works really hard," said Borini.
"We never gave up, played our game throughout the 120 minutes and got our reward at the end."
Sunderland will meet Manchester City in the final at Wembley on March 2.