A year ago, Orlando Arcia was regarded as a slick fielder with modest offensive promise. Alex Reyes and Jose De Leon were two raw but intriguing arms in Short Season Class A. A.J. Reed, the reigning college player of the year, was a second-round pick who posted a solid pro debut. Max Kepler was known as the best German prospect ever yet little else.
Fast forward 12 months, and Arcia (Brewers) not only is one of the game's best shortstop prospects, but one of the best overall prospects. Reyes (Cardinals) and De Leon (Dodgers) are two of the most coveted pitching prospects in baseball. Reed (Astros) put up better numbers than anyone in the Minors last season, and Kepler wasn't far behind.
Those are just five examples of how prospects' stock can be extremely volatile. Here are 10 players (listed alphabetically) poised to surge in 2016:
Anthony Alford, OF, Blue Jays: Though he signed for $750,000 as a third-round pick in 2012, he spent most of 2012-14 playing college football at Southern Mississippi and Mississippi. That cost him more than 1,000 at-bats, which often kills the careers of two-sport players, but he committed to baseball full-time and showed surprising polish and instincts while batting .298/.398/.421 with 27 steals between two Class A stops in 2015. He could wind up as a center fielder with plus-plus speed and solid or better tools across the board.
Jake Bauers, 1B/OF, Rays: Tampa Bay blew the Wil Myers trade last December when it didn't keep Trea Turner and Joe Ross after getting them from San Diego and instead shipped them to Washington for Steven Souza. The one positive from the Rays' perspective was that they did hold onto Bauers, who has a sweet left-handed swing and developing power. He handled Double-A pitching at age 19 and showed some aptitude as an outfielder in the Arizona Fall League.
Bobby Bradley, 1B, Indians: He ran away with the Class A Midwest League home run race in his first full pro season, smacking 27 roundtrippers this summer -- the most by a MWL teenager since Miguel Sano hit 28 in 2012. Bradley, who won the Rookie-level Arizona League triple crown in his 2014 pro debut, might be the best power prospect in the Minors by the end of 2016.
Anderson Espinoza, RHP, Red Sox: Boston thought he was the top pitcher on the international amateur market when it paid him a Venezuelan-record $1.8 million bonus in July 2014, but it didn't realize Espinoza was this good. He reached Class A at age 17 in his pro debut, posting a 65-14 K-BB ratio along the way, hitting 100 mph with his fastball and displaying advanced secondary stuff and command. He also earned some hyperbolic Pedro Martinez comparisons.
Josh Hader, LHP, Brewers: Considered the third-best prospect Milwaukee received when it traded Carlos Gomez and Mike Fiers to Houston in July, Hader drew Madison Bumgarner and Chris Sale comps while leading the Arizona Fall League with a 0.56 ERA. He looks like he could help immediately as a reliever with a mid-90s fastball, nasty slider and deceptive delivery, but he offers more long-term value as a No. 3 starter.
Ke'Bryan Hayes, 3B, Pirates: One of the best pure hitters in the 2015 Draft, he could prove to be a steal as the 32nd overall pick. A more well-rounded player than his father Charlie, who spent 14 seasons in the Majors, Ke'Bryan has solid power potential and has worked hard to become a quality defender at the hot corner.
Francis Martes, RHP, Astros: Houston's pro scouting department has a knack for finding hidden gems in the lower levels of the Minors, such as getting Martes in the Jarred Cosart trade with Miami in July 2014. He had yet to pitch above Rookie ball at the time but progressed to Double-A as a 19-year-old in 2015, touching 98 mph with his fastball and backing it up with a devastating power curve. The Astros were able to include Vincent Velasquez and Mark Appel in December's Ken Giles deal because Martes could be better than either of them.
Harold Ramirez, OF, Pirates: Pittsburgh has a logjam of legitimate center fielders, starting with Andrew McCutchen, Starling Marte and Gregory Polanco in the big leagues and blue-chip prospect Austin Meadows not too far away. The Pirates have another one in Ramirez, who hit .337/.399/.458 in Class A Advanced at age 20 despite battling leg injuries. He's another pure hitter in a farm system loaded with them, and he has yet to tap into what could be average power potential.
Cody Reed, LHP, Reds: He's the best of all the prospects rebuilding Cincinnati has acquired this year, coming from Kansas City in the Johnny Cueto trade in July. Reed went 3-10 with a 5.62 ERA in his first two pro seasons before going 13-9 with a 2.41 ERA and reaching Double-A in 2015. He's a lefty who throws strikes and can miss bats with three pitches: a lively 91-97 mph fastball, a darting slider and an improving changeup.
Forrest Wall, 2B, Rockies: An advanced hitter with well above-average speed, he fits the profile of an offensive-minded second baseman. If Wall's quick bat translates into average power, he could do a lot of damage when he gets to Coors Field. The biggest question is his arm, diminished by a pair of surgeries as an amateur, but the consensus is that he'll be able to get by at second rather than having to move to center field.
Jim Callis is a reporter for MLB.com. Follow @jimcallisMLB on Twitter. This story was not subject to the approval of Major League Baseball or its clubs.