User blog comment:B214/Volume 23 discussion blog/@comment-31764731-20170417191738/@comment-10330822-20170417221906

As far as we know, he can still have a match against her even as her Pawn. She'd probably just need a stand-in for the match, like how Irina stood in as Riser's Bishop during his match with Rias.

Besides, I feel Issei isn't going to either need nor want to face her after this tournament. Issei seems intent on proving that he is every bit Rias's equal, and suitable to be her husband, and I feel he wants to beat her to prove that to everyone.