Noise from Lower Unit

[Perry Wong]

I have a '97 Evinrude 70hp on my boat. I noticed that when I rapidly pull back on the throttle from being on a plane a noise coming from the lower unit. It sounds like the water is forcing the prop to continue turning even though the engine speed (RPM) have come back down to idle. Does that sound like a bearing in the gear case or lower unit? Any suggestions. I plan on taking the motor in for service but thought someone might be able to diagnos the problem. Thanks in advance.