pertempuran ini meletus di lembah pegunungan belasitsa dan ograzhden di dekat desa klyuch.
pertempuran yang menentukan berlangsung pada 29 juli ketika jenderal romawi timur nikephoros xiphias melancarkan serangan belakang.
bulgaria mengalami kekalahan besar; tentara bulgaria ditangkap dan dibutakan atas perintah basil ii, yang kemudian dikenal dengan nama "pembantai bulgar."
samuel berhasil selamat, namun meninggal dua bulan kemudian karena serangan jantung, yang konon karena melihat tentara bulgaria yang telah dibutakan.
meskipun pertempuran ini tidak mengakhiri kekaisaran bulgaria pertama, pertempuran ini mengurangi kapabilitas negara tersebut dalam menahan serangan romawi timur.
penerus samuel tidak dapat menahan serangan romawi timur, dan akhirnya pada tahun 1018 kekaisaran bulgaria dihancurkan oleh basil ii.
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