Transmission Downshifts Hard

I've noticed that my Fusion will downshift really hard into what I believe is 2nd gear after I slow down. This problem only occurs when I've been driving on the freeway (driving 65-70MPH) and then exit. It's a very jerky shift and it occurs around 15MPH. I've tried different techniques of braking and coasting to stop it for occuring, but it happens every time.

Any idea what may be causing this?