Projecting how top prospects will perform in their rookie campaign is difficult. In 2017, Matt Olson and Rhys Hoskins did a lot of producing with little opportunity, while Yuli Gurriel hit only 18 home runs in 139 games as a first baseman.Sometimes limited opportunities don't kill a player's value, while full-time opportunities won't necessarily guarantee that a rookie will be fantasy relevant, either. Trying to balance potential impact and possible opportunities is the key to projecting who will be the best rookies to own in fantasy.Ronald Acuna, OF, Atlanta BravesCurrent Player Comparison: Justin UptonAcuna hits for both power and batting average, he gets on base and he has enough speed to contribute a few stolen bases as well. With an ADP of 126, according to FantasyPros, he is a better selection with more upside than players like Adam Jones, Ian Desmond and Ender Inciarte.Shohei Ohtani, SP/DH, Los Angeles AngelsComp: Yu DarvishOhtani's 95-plus mph fastball, multiple breaking balls and a splitter that can be unhittable in what should be 165-180 innings pitched at potentially a strikeout per inning makes him an impact rookie in 2018.Lewis Brinson, OF, Miami MarlinsComp: Keon BroxtonBrinson has the most impressive physical tools and the highest ceiling of any 2018 rookie. About 20 home runs and 20 stolen bases isn't outside the realm of possibility for the "toolshed talent." His ADP of 312 makes him one of the best values in this year's rookie class.Victor Robles, OF, Washington NationalsComp: Christian YelichRobles won't break camp with the Nationals but his five-tool ability makes him fantasy relevant upon promotion. Draft and stash him.Luiz Gohara, SP, Atlanta BravesComp: Robbie RayGohara's fastball has tickled triple-digits and his swing-and-miss slider should make him an impact rookie as early as mid-May.Franklin Barreto, SS/2B, Oakland AthleticsComp: Josh Harrison/Brandon PhillipsBarreto has enough power and speed to be relevant as an SS/2B with an ADP (513) that makes him a value at half the price.Willie Calhoun, 1B/OF, Texas RangersComp: Kyle SchwarberCalhoun can rake but he can't really field or run. Within reach is 25-30 home runs and a .280 batting average. The question is when does Texas promote him and where do they play him?Dustin Fowler, OF, Oakland AthleticsComp: Denard SpanFowler doesn't have explosive tools but he could contribute 10-15 home runs and 10-15 stolen bases with an ADP (447) that makes him an intriguing flier in deeper leagues.Jesse Winker, OF, Cincinnati RedsComp: Hunter Renfroe/Adam DuvallWinker needs to find at bats in a crowded Reds outfield, but the home run potential will play as a rookie when he does.Gleyber Torres, SS/2B, New York YankeesComp: Daniel MurphyTorres has a high floor with a limited ceiling because of his lack of stolen base ability. He should handle major league pitching just fine, the question is if the power develops in time to be relevant in fantasy for 2018.Francisco Mejia, C/OF, Cleveland IndiansComp: Willson ContrerasMejia can flat-out hit. The question is when he will do it at the Major League level and what fantasy position will he qualify at. As a potential catcher he is a draft and stash.Jorge Alfaro, C, Philadelphia PhilliesComp: Robinson ChirinosIt looks like Alfaro will break camp with the Phillies as their No. 1 catcher with the power and at-bats to hit 20 home runs in the friendly confines of Citizens Bank Park. That's good value at around pick No. 300.___This column was provided to The Associated Press by the Fantasy Sports Network, http://FNTSY.com