In his first Major League appearance , he walked the only batter he faced , Anthony Rendon .
The Marlins promoted Wittgren to the major leagues on April 19 , 2016 .
In Wittgren 's first Major League appearance , Wittgren walked the only batter he faced , Anthony Rendon .
The Marlins promoted Wittgren to the major leagues on April 19 , 2016 .