what is the exact meaning of "部長が自分のミス俺のせいにしゃがってさ" in below sentence


I don't understand exactly the meaning of "部長が自分のミス俺のせいにしゃがってさ" the whole
sentence is: 今日もさ 部長が自分のミス俺のせいにしゃがってさ冗談じゃ ないよ お前 部下をかばってこそ 上司だろ おい!

the meaning in the text is: today, the head of my department tried to blame me
for his screwup. “This is wrong!” I said. “A chief is a chief because he
protects his subordinates!”

but I want to know the grammar points of the aforesaid sentence and if the
meaning is correct or not.




If it's しゃがる that's troubling you, it's not しゃがる but しやがる, which is し (masu-
stem of する) + [やがる](https://japanese.stackexchange.com/q/4236/5010).

If it's てさ that's troubling you, see: [て form at end of phrase but not being
used for requests](https://japanese.stackexchange.com/q/60762/5010)

This sentence uses the AをBにする ("to make A B", "to turn A into B", "to pretend
A as B") construction, although を has been omitted:

> 部長が自分のミス **を** 俺のせいにしやがった。  
>  The chief turned his own error into my fault.  
>  → The chief blamed me for his own mistake.




If it's しゃがる that's troubling you, it's not しゃがる but しやがる, which is し (masu-
stem of する) + [やがる](https://japanese.stackexchange.com/q/4236/5010).

If it's てさ that's troubling you, see: [て form at end of phrase but not being
used for requests](https://japanese.stackexchange.com/q/60762/5010)

This sentence uses the AをBにする ("to make A B", "to turn A into B", "to pretend
A as B") construction, although を has been omitted:

> 部長が自分のミス **を** 俺のせいにしやがった。  
>  The chief turned his own error into my fault.  
>  → The chief blamed me for his own mistake.

