The left-back’s classy 25th-minute strike was sandwiched by Sadio Mane’s opener and Mohamed Salah’s close-range finish as the Reds raced into a three-goal lead in Wednesday’s Champions League Group E game at Anfield.
Salzburg were back on terms by the hour mark, however, thanks to Hwang Hee-Chan, Takumi Minamino and Erling Haaland.
But the European champions responded to that setback and claimed a vital victory courtesy of Salah’s clinical Kop-end finish.
Robertson’s was arguably the pick of the seven goals, though, the Scotland captain bursting in-field and feeding Jordan Henderson before continuing his run as the captain played in Trent Alexander-Arnold down the right.