Their sustained ability is unknown, not more, probably less, while in defense i a huge amount less. A lot of rookies have come up, shown brightly then gone dim or burned out, recently.
julizn fielding at secone is a nail biter with each throw, Wallner in Right is a degrade from Kepler, Larnach and Miranda's boats have probably sailed.
There is a LOT of play this rookie, play that rookie, and the past years have shown that to be an empty promise.
We are trying to win the division this year, next years Spring Training will weed out some mystery.
Wishful thinking has a smaller sucess rate than shooting craps.