In this Perek, the first Mishnayos deal with 2 Nezirim, one of whom is Tomei, but we do not know which, and what they should do.
The second Mishna on 59b speaks about a Nozir who is Sofek Tomei as well as Sofek Metzoro.
Is this Sofek Tomei the same as the first Mishnayos (i.e. he was one of a pair) or an independent sofek?
If he was one of a pair, presumably when the Gemoro states his procedure, it is subject to the discussion in the earlier Mishnayos.
If he was independent, why don't we just say "Sofek Tuma Birshus HaRabbim Tohor", or in Reshus HaYochid Tomei (i.e. why do we have to be worried in case he is a Nozir Tohor and cannot have a haircut, but he may be a Nozir Tomei etc). As Tosfos on 57a explains we would learn from Sotah, but in the case of a pair of Nezirim each one does not have an independent sofek (i.e. it is not POSSIBLE for them both to be Tomei).
Mark Bergman, Manchester, England
It is possible for one Nazir of the pair to be Safek Tamei in the case when his partner was not a Nazir originally, in which case the procedure of the Mishnah does not apply.
However, there are other Sfeikos which are not decided by the rule of Safek Tum'ah b'Reshus ha'Rabim. For example, in a Sfeika d'Dina, such as a Machlokes as to the size of a k'Zayis, the Nazir will be Safek Tamei.