If this was at normal times then Rafael wouldn't be affected by Saske's dark energy.
But Rafael was now squeezing everything from him just to defeat Saske he was now on the verge of collapsing only with his will to win was he able to continue fighting.
For Saske he looks like he suffered far more that Rafael since Rafael's holy like energy were able to penetrate his dark armor but even though he suffered numerous cuts it was only external injury.
Compared to Rafael's agonizing internal bleeding it was nothing.
So Saske is quite confident he would be able to defeat Rafael.
Rafael also knew this that is why he was using all of his power just to take down Saske but he could only inflict minor injuries.
He then retreats away from him as he started to condense his energy to his sword since he was nearing his defeat he wanted to go out with a boom.
Saske suddenly shivers as he his instinct told him that Rafael was planning something dangerous.