Birthday boy Owen Farrell gave a clenched fist salute after nailing the last-gasp kick which gave Saracens a sensational win.
Trailing by 12 points with four minutes left the five-time Premiership champions looked dead and buried.
Saracens boss Mark McCall even admitted the game had “gone” after a “horrible period” either side of half-time in which his side shipped 26 unanswered points.