A1 has the ball out of bounds for a throw-in and is being guarded by B1. Before releasing the ball, A1 loses his/her balance, reaches out and puts his/her hand on B1 (who is inbounds) in an effort to regain his/her balance.
Throw-in violation by A1. A1 is required to remain out of bounds until releasing the throw-in pass. When A1 touches an inbounds player, he/she has inbound status. However, if the contact on B1 is illegal, a personal foul shall be called.