reading comprehension - What does 斜めに流すこと mean?

I have problems with understanding a particular line from a Japanese novel and need some help. The scene is about a little girl practicing her sword skills with her father. Just before the line I had problem with, the girl was parrying a diagonal slash from her father (対敵の振り下ろす袈裟切りの一刀に立ち向かう).

Then comes this line: 成長途上の体で受けきるには荷が勝ちすぎる一撃を、しかし少女は全身のバネを駆使して斜めに流すことによって凌ぎ切った。

My problem is identifying what 「斜めに流すこと」 is referring to?

1. 
   

   Is it referring to the diagonal slash? (that is to say, 'as a result of the slash being diagonal, the girl was able to deftly use the elasticity of her whole body to stop it')

   
   


2. 
   

   Or is it referring to the stance the girl is taking?

   
   

My current belief is (1), but I'm not sure.

Thanks in advance.