He has to hit the cover off the ball
In order to win a roster spot, Bart not only has to have a solid spring, he has to absolutely dominate opposing pitching. We’re talking close to 10 home runs and a batting average in the stratosphere.
He has to demonstrate beyond a shadow of a doubt that he is ready for the big leagues.
He would have to have a Chris Marrero or Kris Bryant-like spring and even then it would be tough for him to find his way onto the Opening Day roster. The organization probably wants to ease him into the big leagues rather than force him into the mix during a rebuild.
But it goes without saying that Bart would have to hit like a maniac to earn a spot on the Opening Day team.