To be fair, there were plenty of near misses at Hillsborough in that end at previous FA Cup semi finals. Leeds fans in the Leppings Lane end in 1987 against Coventry will testify to this. However, the main one prior to the Hillsborough disaster was in 1981 when Spurs fans were in there against Wolves. 38 fans were injured and some ended up with broken limbs in the crush, and it was only the actions of the police in opening the gates at the front of the stand (in stark contrast to 8 years later) to ease the pressure and allowing hundreds of Spurs fans to sit round the perimeter of the pitch to watch the game that averted a much bigger disaster. You can watch the footage of it unfolding here: