Kote during the retraction
Another option, that requires impeccable timing (like all techniques!) is to irimi directly to the side of the incoming jab and deflect with the lead hand. Maintain the contact as the jab begins to retract and step in with the rear foot. At the same time apply Kotegaeshi with the rear hand in a tight circle against the fist. The rear foot should be directed into the corner of the jabbing shoulder. (kind of like a second irimi for a sumi-otoshi, with the kotegaeshi. I've seen Pat Hendricks Sensei do this at a seminar with positive effect.