It's highly ridiculous the argument that's gone on in here, debating a definite handball by Perisic.
His reaction, after a heightened state of defence, was to move his hand TOWARDS the ball instinctively as otherwise it would have passed him and threatened the goal behind him. The fact that Matuidi misses the ball is what causes that instinctive defensive action!
Was it an accident? That would be a whole different argument based on 'nature vs nurture'!
The fact is, it happened and prevented a possibility of goal bound action.
Absolutely right to change his mind on it and I saw what the ref saw.
Excellent call.