Sergio Floccari struck deep into stoppage time to send Lazio into the Italian Cup final after a 2-1 second-leg win on Tuesday as Juventus saw their hopes of a domestic double destroyed.
Lazio, who drew 1-1 at Serie A leaders Juve in last week's semi-final first leg, seized the initiative eight minutes after the break through Alvaro Gonzalez's header before Arturo Vidal equalised in injury time and striker Floccari had the last word.
Juve had come into the game under pressure after a wobble at the top of Serie A and widespread criticism following coach Antonio Conte's verbal attack on match officials at the weekend.
AS Roma are leading Inter Milan 2-1 after their semi-final first leg last week but the return at the San Siro does not take place until April 17.
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