I'd be inclined to step around and go for Kotegaeshi, in a similar fashion to the shomen uchi form.
A) because he's naturally going to off balance if your no longer at his point of attack
B) It takes you out of the line of further attacks
C) Its easy and effective, and can go to either a pin or a release, depending on where you want to go.
and of course
D) Kotegaeshi rocks.