Lars knew this attack would be a dangerous one, as you realize that he had his shield directly in your face. His hand-eye coordination is very bad, otherwise he would have retracted his shield along with his sword.
Knowing that this window of opportunity would most likely never show up again, you take it! Your sword went right around his shield. LARS HAS LOST HIS SHIELD ARM! Bors doesn't even have time to call hold as Lars gets rid of his shield faster than you can kepp track of. The fight continues!