Complex sentence: Unfortunately for Mets fans, the Celtic Pagan spell cast by Kennealy-Morrison upon the New York Yankees did not work during that year's World Series, as the Mets succumbed to the Yankees four games to one in the 2000 Fall Classic.
Split into simpler sentences: Unfortunately for Mets fans, the Celtic Pagan spell cast by Kennealy-Morrison upon the New York Yankees did not work during that year's World Series. The Mets succumbed to the Yankees four games to one in the 2000 Fall Classic.