Sephiroth may be renowned for his strength, but he's also an agile man. The rage that lends ferocity to Connor's attacks also makes them easy to read, and the better part of those blows are simply avoided with a quick pivot or a duck to one side. Connor clearly has some skill, but it's also clear he isn't in his right mind; something animal has overtaken him.

One of those kicks does land successfully, and Sephiroth stumbles back. As he starts to recover, he draws the machete-- it doesn't have the long reach of his usual weapon, but if Connor retains any sense of self-preservation, it should give him pause.