Arsenal will play London rivals Chelsea in the FA Cup final on May 27 after beating Manchester City 2-1 following extra time in the semi-final at Wembley on Sunday.
Arsenal had to come from behind after Sergio Aguero scored his 30th goal of the season for City in the 63rd minute, racing away on to a pass from Yaya Toure.
Spanish international Nacho Monreal equalised nine minutes later, from a cross by Arsenal's other wing back Alex Oxlade-Chamberlain.
In the 11th minute of extra time, just after Aguero was taken off, Alexis Sanchez scored the winner.
The result gave manager Arsene Wenger, an FA Cup winner six times, a welcome boost in a season that many supporters would like to be his last at the club.