WATCH: Joshua Baez becomes first MLB player to hit 3 homers in debut

Cardinals rookie outfielder Joshua Baez made MLB history by becoming the first player to hit three home runs in his big league debut.

​Cardinals rookie outfielder Joshua Baez made MLB history by becoming the first player to hit three home runs in his big league debut.  WNT Cardinals rookie outfielder Joshua Baez made MLB history by becoming the first player to hit three home runs in his big league debut.