It broke out within seconds of the referee's starting whistle. Compare it to the moving silence at Anfield before Liverpool's clash with Manchester City hours earlier.
It was as if Wembley was commemorating and Anfield was mourning.
There were those who understood the clapping. But some expressed that it seemed to celebrate the fight for justice rather than commemorate the dead.
25 years on and the wounds of Hillsborough will never quite heal completely.