全戦 ぜんせん全勝 ぜんしょうではありませんでした
zensenzenshōdewa arimasendeshita

Noun
Desu Copula

The polite, past negative form of 全戦全勝

1. Was not a complete victory in all battles.; Was not undefeated in all wars.

Past/Perfective
Negative
Polite
Formal Register