Whether acquired in the late rounds of drafts or via the waiver wire during the season, rookies can play a major role in separating very good fantasy teams from championship squads. After all, the cost to add these players tends to be minimal, and being that your league mates will also be in pursuit of the next impact rookie, making educated choices becomes all the more important. So with the 2015 season almost in the books, it is time to unveil the All-Rookie Team, and I'll make an educated guess that one or more of these players resides on the roster of the vast majority of first-place fantasy teams.
Catcher: Kyle Schwarber
The No. 4 overall pick in the 2014 MLB Draft, Schwarber faced high expectations upon his big league debut in mid-June, and aside from a mediocre batting average, he's met those expectations. His power is legit (34 homers in 147 career Minor League games and 16 homers through 67 big league games this season), and considering that he hit .333 in the Minors, there's reason to believe that he can improve in that category going forward. Whether or not Schwarber will start enough games behind the plate next season to maintain his catcher eligibility beyond 2016 remains to be seen, but fantasy owners will be able to enjoy at least one full season with him as their starting backstop.
First base: Justin Bour
After five seasons in the Minors, Bour finally received a big league opportunity with the Marlins in 2014, but it was limited in length (74 at-bats). This year, thanks to his solid power production (23 home runs through 126 games), the 27-year-old has spent nearly the entire season in the Majors. Bour has been one of the few bright spots in a Miami lineup that has struggled to score runs on a consistent basis in 2015, and he's certainly performed well enough to enter next season as the club's starting first baseman against right-handers.
Second base: Addison Russell
The key piece that headed to Chicago in the trade that sent Jeff Samardzija and Jason Hammel to the A's last July, Russell has posted decent but not overly impressive numbers in his rookie season. Despite showing power, with 13 homers through 139 games, the 21-year-old has somewhat surprisingly struggled in the batting average department, this after hitting .301 during his Minor League career. Still, Russell has age and a stellar Minor League track record on his side, so it would not be surprising to see him significantly improve his overall stat line in 2016. The Cubs second baseman will make for an intriguing buy-low pick in drafts next spring.
Shortstop: Carlos Correa
In most other seasons, Francisco Lindor would have been the clear choice here. Unfortunately for Lindor, however, a certain 21-year-old shortstop on the Astros has lived up to all of the hype that surrounded his early-June callup and has proven why he was deserving of the No. 1 overall selection in the 2012 MLB Draft. Correa's ability to contribute at a high level in all five standard rotisserie hitting categories is a big reason why he is such a valuable fantasy asset, especially in long-term keeper leagues.
Third base: Kris Bryant
Not only has Bryant been the top rookie third baseman in fantasy baseball this season, but a strong case can be made for him as a top-five overall third baseman. The 23-year-old's rookie campaign didn't begin until mid-April, but it didn't take him long to adjust to big league pitching. Bryant batted .318 in April before finding his power stroke in May, launching seven home runs. Considering that he slugged 43 homers in 138 Minor League contests in 2014, fantasy owners should not be surprised if his home run total steadily rises in future seasons. Even in non-keeper formats, Bryant will be worthy of a top-30 overall pick on draft day 2016.
Outfield: Billy Burns
Owners in need of speed early in the season found their answer in Burns, who swiped nine bags in May following his callup early in the month before tallying another seven in June. But Burns has been more than just a speedster this season, batting .294 through 123 games to go along with the 26 steals, so those who invest in the A's outfielder next year will be able to do so only at the expense of homers and RBIs. Looking ahead to 2016 drafts, the 26-year-old will be an attractive mid-round option for fantasy owners who choose to load up on power early.
Outfield: Delino DeShields
Continuing on the speed theme, DeShields, who compiled 241 stolen bases in 503 career Minor League games, emerged as a reliable source of steals in his first big league season, especially during the month of May (10 steals). His improved hitting eventually earned him regular at-bats, and though he hasn't been quite as consistent at the plate in the second half -- registering a .330 OBP, compared to a .360 OBP prior to the All-Star break -- the 23-year-old still has plenty of time to make the necessary adjustments. At this point, a return trip to the Minors is highly unlikely for DeShields, so fantasy owners, even those in non-keeper mixed leagues, can feel free to spend a mid-round pick for his services next season.
Outfield: Randal Grichuk
Despite missing time due to a back injury and later a right elbow injury, Grichuk has been a solid contributor to both the Cardinals and fantasy teams in his first full big league season -- tallying 17 home runs through 100 games. The 24-year-old hit a combined 47 homers in the Minors from 2013-14, so the power production is no aberration. The biggest question regarding Grichuk for 2016 centers around his role with the team and whether he will receive enough at-bats to be worthy of consideration in mixed-league drafts. Fantasy owners should keep an eye on this situation heading into Spring Training.
Starting pitcher: Noah Syndergaard
Although Syndergaard has struggled at times this season, his overall stat line -- which includes a 3.34 ERA, 1.08 WHIP and 9.8 K/9 rate through 23 starts -- speaks for itself. The fact that many young power pitchers experience control problems upon their first taste of the big leagues makes Syndergaard's 1.9 BB/9 rate all the more impressive. For now, the safe approach for fantasy owners is to value the 23-year-old as a strong mid-rotation starter in non-keeper mixed leagues, but he could approach ace status as soon as next season.
Starting pitcher: Lance McCullers
McCullers opened the 2015 season at Double-A Corpus Christi, but after pitching to a 0.56 ERA to go along with 48 strikeouts across 32 innings, it became evident that he was big league ready. The transition has been a rather smooth one for the 22-year-old righty, who boasts a 3.21 ERA, a 1.17 WHIP, a 7.5 H/9 rate and a 9.2 K/9 rate through 21 starts. Expect McCullers to enter the 2016 campaign with a secure spot in the Astros' starting rotation, and he's done more than enough to earn a mid-round selection in mixed league drafts.
Closer: Roberto Osuna
Toronto's ninth-inning situation was in flux for much of the first half, but when the club finally gave Osuna an extended look in the closer's role, he delivered, converting all 14 of his save chances from the beginning of July through the end of August. He has since notched four more saves in five opportunities and carries a 2.36 ERA and a 0.87 WHIP through 66 appearances this season. When discussing the top waiver-wire finds of the 2015 fantasy season, Osuna certainly belongs in the conversation.
Zach Steinhorn is a fantasy writer for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.