From the Super Mario Wiki
Peach executing her Super Peach Spin
in Mario Power Tennis
Super Peach Spin is Peach's Offensive Power Shot in Mario Power Tennis. Peach closes her eyes, spins very fast and hits the ball with the power of love. This will knock the opponent back a few inches, then attract the opponent to the net, leaving them open to Lob Shots and causing them to lose any Power Shots that they are storing. It has an amazing curve, in fact the best curve in the game. The recovery time is very slow, though. It is possible for Peach to miss the ball while performing the shot.