しかし、木沢長政は管領細川晴元、三好長慶と対立し、天文11年(1542年)、河内太平寺の戦いで敗死する。

But Nagamasa KIZAWA was in opposition to Kanrei (shogun's deputy), Motoharu HOSOKAWA and Nagayoshi MIYOSHI and in 1542, he was defeated and killed in the battle of Kawachi Taihei-ji Temple. - Wikipedia日英京都関連文書対訳コーパス

長慶は長じて智勇兼備の武将に成長し、細川氏の家臣として木沢長政討伐（太平寺の戦い）をはじめ、細川氏綱や遊佐長教らとの戦いで多くの武功を発揮した。

Nagayoshi became an intelligent and brave busho (Japanese military commander) left a lot of military exploits as a vassal of the Hosokawa clan, including at the suppression of Nagamasa KIZAWA (the battle of the Taihei-ji Temple), battles against Ujitsuna HOSOKAWA and Naganori YUSA. - Wikipedia日英京都関連文書対訳コーパス

弟の三好義賢（阿波）や十河一存（讃岐）、安宅冬康（淡路）らと協力して、木沢長政（太平寺の戦い）、三好政長らの父の仇の敵勢力を次々と破った。

In cooperation with his brothers Yoshikata MIYOSHI (Awa), Kazumasa SOGO (Sanuki) and Fuyuyasu ATAGI, he beat the forces of Nagamasa KIZAWA (in the battle of Taihei-ji Temple) and Nagamasa MIYOSHI one after another, both of whom had been his father's enemy. - Wikipedia日英京都関連文書対訳コーパス