back court violation in bounds question

[daveg144]

In seven years I've never had a question on this...but now I do.

Team A has possession in the front court. A1 makes an errant pass to A2 and the ball goes into the backcourt. A2 chases it down but doesn't touch it until it is just inside the free throw line (inside the lane). The officials put the ball in play on the sideline, just inside the free throw line (extended). B's coach wanted the ball out of bounds on the baseline, not the sideline.

I've always inbounded the ball on the side after a backcourt violation and after a quick look in the book, I can't find a clear answer.

What do you all say?