1. Kurosaki Ichigo (Bleach)
Even if ichigo don't seems to have to have a chance against saitama, you can't be so sure about this.
Because what we learned of ichigo that he never ever give up, with his hollow form and the hollow ichigo the quincy power and more he can give saitama a really hard time.
2. Sosuke Aizen (Bleach)
Aizen is feared in his own series and even in other series, he is also ranked to be the villain of villain's.
And with his many and many kido's he might beat saitama even without a zampakto.