"How could this happened?" Shane and Brent had difficulties processing what was happening to them. They knew that Hespar was strong, but not to this level. They find it hardly believable that it only takes Hespar a single swing of his sword to deflect their attack.
Furthermore, it was done with ease.
For a moment, they're wondering if this strength comes from Hespar's Aura or perhaps the enhancement from his treasured sword, Hatti. As a matter of fact, both of their guesses were wrong.
It wasn't because Hespar was too strong for them but because they lacked the understanding of the mastery of the sword. Their strike was powerful, but only in sheer force. It lacks the depth necessary to create an attack that is straightforward but difficult to receive.
This is almost the same as the profession of a Processor, a Physician, or a Chef. While they're all capable, one could hardly produce or refine better products without a sufficient understanding of their craft.