When you are at the kitchen line and your opponent hits a lob over your head, how do you respond?
If you see your partner by your side at the kitchen line, one of you may choose to make a run for it. Never back pedal. Side step to the baseline, or make a U-turn and move to the back, perhaps in time to attempt a blind return shot. Most often, we just let it go and hope it lands out. Executing an effective lob is difficult and a pretty low percentage shot so don’t obsess if your opponents get one now and then.
If you do not see your partner by your side, you should assume s/he may be in position to get the shot. So, help your partner by ducking immediately, giving him a full court to work with.
If you have a good partner who was able to move from his spot across the back to get the lob behind you, he will yell “Switch” which is your cue to stay at the kitchen line but quickly move to cover the other side.
So, duck to get out of the way, or move to cover the other side of the court if your partner commands.