Australia had lost just one of their previous 14 Tests against Argentina, but in San Juan on Saturday they were on the end of hiding.
It was in a football cage in Roehampton where Ryan Sessegnon dreamt of emulating Gareth Bale, having watched on television as the then Tottenham wide man took on Inter Milan’s defence single-handedly at White Hart Lane.
Gallagher is back at Chelsea after a standout loan spell at Crystal Palace last season.
A brace from Ante Rebic helped defending Serie A champions to an opening day win against Udinese, sealing a 4-2 victory at San Siro.