The Batter has to immediately silence the urge to keep going because the Drifter was presenting him a clear opportunity to kill them. He's never been above taking those moments of vulnerability to kill someone if needed. So instead he just breathes.

"I am fine." Of course there's a nasty welt across the palm of the Batter's hand when he holds it up for the Drifter to see, since it's pretty obvious they're worried. But he can heal that in a minute. "I intended for that to happen."

So it's nothing to worry about. If he had caught the sharp end of the Drifter's blade then it would be his fault his trick failed. That's all.