Rubuta ci gaba don wannan sakin layi - Bayan mutuwar Pericles, Athenians sun juya wani abu game da tsare-tsarensa, dabarun karewa da kuma dabarun da ya fi dacewa na kawo yaki ga Sparta da abokanta. Tashi zuwa mahimmancin mahimmanci a cikin dimokiradiyya na Atheniya a wannan lokacin shine Cleon, jagora na abubuwan hawkish na dimokiradiyya na Atheniya. A karkashin jagorancin wani sabon janar mai basira Demosthenes (ba za a rikita shi da mai magana da yawun Athens Demosthenes ba), Atinawan sun sami nasarar wasu nasarori yayin da suka ci gaba da hare-haren jiragen ruwa a Peloponnese. Athens ta fadada ayyukan sojinta zuwa Boeotia da Aetolia, ta dakatar da tawaye na Mytilenean
kuma ya fara ƙarfafa posts a kusa da Peloponnese. Ɗaya daga cikin waɗannan sansanonin yana kusa da Pylos a kan ƙaramar tsibiri da ake kira Sphacteria, inda yaƙin farko ya juya ga taimakon Athens. Matsayin Pylos ya buga Sparta a inda ya fi rauni: dogaro da shi ga helots, waɗanda ke kula da filayen yayin da 'yan ƙasa suka horar da su don zama sojoji. Helots ya sa tsarin Spartan ya yiwu, amma yanzu post daga Pylos ya fara jawo hankalin masu guduwa. Ƙari ga haka, tsoron tawaye na 'yan Helot da ke kusa da Atina ya ƙarfafa 'yan Sparta su ɗauki mataki. Demosthenes, duk da haka, ya rinjayi Spartans a yakin Pylos a 425 BC kuma ya kama wani rukuni na sojojin Spartan a kan Sphacteria yayin da yake jiran su mika wuya. Amma, bayan makonni, Demosthenes ya kasa kashe mutanen Spartan. Bayan ya yi alfahari da cewa zai iya kawo karshen al'amarin a Majalisar, Cleon marar gogewa ya sami babban nasara a yakin Sphacteria. A wani abin mamaki, 'yan Spartan guda 300 da sojojin Athens suka kewaye su suka miƙa kai. Hoton Spartan na rashin cin nasara ya sha wahala sosai. Atinawan sun tsare 'yan gudun hijirar Sphacterian a Athens kuma sun yanke shawarar kashe Spartans da aka kama idan sojojin Peloponnesian suka sake mamaye Attica.