Real Sociedad's Inigo Martinez scored from inside his own half in the Basque derby on Sunday, but brace made sure Athletic Bilbao earned a 2-1 away win in La Liga.
Centre back Martinez let fly from inside the centre circle catching Gorka Iraizoz off his line, the visiting keeper perhaps distracted after one of his defenders had just been carried off on a stretcher, and the ball dipped under the crossbar.
Llorente then struck a superb volley to restore Bilbao's advantage in the 71st and earned under-pressure Argentine coach Marcelo Bielsa a first league win this season.
Bilbao climbed out of the bottom three to five points from six games, two behind their north-coast neighbours in ninth.
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