Blow-by-blow: talking about anything in detail. 最开始是用来指 | Desvl English Tips

Blow-by-blow: talking about anything in detail.
最开始是用来指讲解拳击比赛(give an account of a prizefight)，最早可见于1922年 The Wireless Age:
Like a hungry kitten loves its saucer of warm milk, so do radio fans joyfully listen to the blow-by-blow broadcast description of a boxing bout.
这里就是在说，通过录音机，粉丝们连每一拳(blow)怎么打的都知道得一清二楚。
在拳击外的例子比如
Prados offers a good blow-by-blow account of the great naval battle [in his book]. –The Washington Times
（感谢订阅者投稿）
图片来源: https://writingexplained.org/idiom-dictionary/blow-by-blow-account