There's a certain magic in baseball -- and all sports really -- about newly minted stars. Not to diminish the accomplishments of a Joey Votto or a Chris Sale, but on some level, their awesomeness is something we're used to, something comfortable and familiar in the baseball world, but in a way, old hat.
But when the Cody Bellingers and Aaron Judges break out as rookies, there's that additional sense of something new, an excellent player in a space where none existed before. With September call-ups now on the menu as minor league seasons end, it's not a bad time to look at the players with the best chance to fill lineup and rotation holes and be real stars in 2018. Note that I'm focusing on players likely to still have their rookie-eligibility for 2018, so no Rafael Devers or Ozzie Albies here.
Ronald Acuna, CF, Atlanta Braves
Coming into the 2017 season, the Braves, along with prospect-watchers, were waiting to see when Acuna's power would show up. It showed up. Busting through the minors, with a .325/.374/.522 slash line and 21 home runs at three minor-league levels that ZiPS translates to .280/.321/.445, he's put up a fantastic season for a 22-year-old, let alone for a player who doesn't turn 20 until December. Ender Inciarte is a fixture in center field and while it's not written in stone which player moves to a corner to challenge for a Gold Glove there, the Braves essentially need two outfielders. This gives them lots of flexibility how they use Acuna and Inciarte.