I remember a story of a fan who sent a baseball player photo's he took at a couple games. The first one was during a hot streak and the second from a slump.
The fan noticed that his forward foot was pointing to the pitcher during the slump. The batter corrected it and the slump was over.
Every little bit helps. The worst thing Belinelli can do , is to just expect it to end. Good on him for seeking help.