Manchester United came to Camp Nou hoping for a miracle to rival their 1999 Champions League final victory over Bayern Munich.
Then super-sub and now coach Ole Gunnar Solskjaer scored the second of two stoppage time goals to stun the Bavarians and complete an historic treble for the Red Devils.
Twenty years later, trailing 1-0 from the quarter-final first leg, against a Barcelona side unbeaten in their previous 30 Champions League home matches, they needed a similar freak outcome to progress to the semis.
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Barcelona have only twice failed to go through after winning the first leg away from home in Europe, in 41 ties.