@BladeWade: Sorry but nope. Since it's morals off, Shinji uses his shikai to turn Nnoitora into a sitting duck and offs him. The only problem will be hacking through his hierro but Shinji will manage. Especially since he has all the time in the world like this.
With Shinji limited to only base vizard form, I think Nnoitta would win with effort. Although on the defensive, Nnoitra's one rank junior Grimmjow could hold his own without releasing. I think Released Nnoitra's power and particularly his durability would bring him the win.