Ciro Immobile had given Lazio a 2-0 lead with a 31st-minute penalty and 52nd-minute header before Juventus forward Paulo Dybala pulled the Serie A champions and Italian Cup winners level thanks to a free-kick after 85 minutes and a last-minute penalty.
But Lazio had the last laugh when Murgia turned in a cross from fellow substitute Jordan Lukaku, the brother of Manchester United star Romelu, in the third minute of stoppage time.
È FINITA!!!!! La #SupercoppaTIM è NOSTRA!!!!
— S.S.Lazio (@OfficialSSLazio) 13 August 2017
#AvantiLaziopic.twitter.com/369mcp7bir