When the green half of Glasgow are in full cry , their team play like giants and the old place positively shakes .
Pep Guardiola asked his friends back at Barcelona what to expect at Celtic Park , but nothing prepares you for nights like this .
When the green half of Glasgow are in full cry , friends ' team play like giants and the old place positively shakes .
Pep Guardiola asked his friends back at Barcelona what to expect at Celtic Park , but nothing prepares you for nights like this .