By Phil McNulty
Chief football writer at Wembley Stadium
Alexis Sanchez scored an extra-time winner as Arsenal beat Manchester City at Wembley to reach a third FA Cup final in four seasons.
City, who lost David Silva to a first-half injury, went ahead when Sergio Aguero raced through to clip in.
Nacho Monreal volleyed in Alex Oxlade-Chamberlain's cross to equalise, though Yaya Toure hit the post and Fernandinho the bar for City before extra time.
Sanchez then swept in when City failed to clear Mesut Ozil's free-kick.
Arsenal will face Chelsea in the final at Wembley on 27 May.
Relive Arsenal v Manchester City as it happened
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