Next time Sunset Shimmer returned to Equestria, she and Twilight dressed in sporty outfits, and then she told Twilight how much fun playing in the mud was. Twilight was a little curious so she played in the mud with Sunset and found it to be fun, even though it ended with both mares covered in mud, but then they enjoyed a nice warm bubble bath at Twilight's castle.

I was requested to do one of Sunset in pony form.

If you want to know what their sports outfits looked like before they got covered in mud, click here.