Saitou's able to dodge the speedster's assault, for the most part - and when his own speed isn't quite enough to keep him from getting grazed on the arm, he hardly notices; the cut is already mending itself, and even if it's been years since he trained under Shego, the lessons she taught him are never going away.

And first among those was pain tolerance.

As soon as the U-Man turns to engage Hijikata, Saitou seizes on the opening, lunging forward to take a deep slash at his back and get him out of the fight in one stroke, if he can.