throw for a loss
to cause someone to be uncertain or confused
The question threw me for a loss and there was no way that I could reply.

[TahlilGaran] English Idioms Dictionary ▲

throw for a loss
v. phr.
1. To tackle a member of the opposing football team behind the place where his team had the ball at the beginning of the play; push the other team back so that they lose yardage in football.
The Blues' quarterback ran back and tried to pass, but before he could, the Reds' end threw him for a loss.
Compare: LOSE GROUND.
2. informal To surprise or shock (someone); upset; make worry greatly; cause trouble.
It threw Jim for a loss when he failed the test.
Mr. Simpson was thrown for a loss when he lost his job.
Compare: KNOCK FOR A LOOP, SET BACK ON ONE'S HEELS.

[TahlilGaran] English Idioms Dictionary ▲

throw someone for a loss
to cause someone to be uncertain or confused
The question threw me for a loss and there was no way that I could reply.

[TahlilGaran] English Idioms Dictionary ▲