Prospects are like the stock market. One day something looks great, but a day later, that can all change. While there aren't day-to-day fluctuations that might make your outlook on a prospect change so heavily, there are always guys whose stock rises and falls considerably year-to-year and month-to-month.

Today I'm here to take a look at some 2017 MLB prospect risers and fallers as we head into the fantasy baseball draft season. Let's get to it.

Editor's note: Be sure to also check out our 2017 fantasy baseball rankings dashboard. It's already loaded up with tons of great rankings articles and draft analysis. Aside from our tiered staff rankings for every position, we also go deep on MLB prospect rankings, impact rookies for 2017, and dynasty/keeper rankings as well. Bookmark the page, and win your drafts.

Three Up - Rising Prospects

Cody Bellinger, 1B, Los Angeles Dodgers

Adrian Gonzalez has put together a terrific career, but he’ll be 35 years old in May, and the Dodgers are going to have to find a replacement. Luckily, they probably have that guy already. Cody Bellinger was drafted out of high school in the fourth round of the 2013 Draft. He didn’t show much power in his first couple of years in the minors, but his power profile has really come to fruition the last couple of years.

In 2013, Bellinger hit just .210 with one home run in 162 Rookie-ball at-bats. In 2014, Bellinger did hit .312/.352/.474 in 215 Rookie-ball at-bats, but he hit just three home runs. In his first year in Single-A in 2015, Bellinger really put himself on the map. The lefty hit .264/.336/.538 with an impressive 30 HR, 103 RBI and 10 SB to boot. Bellinger did much of the same last season, hitting .263/.359/.484 with 23 HR in 399 at-bats in Double-A. He also had a cup of coffee in Triple-A, blasting three homers in 11 at-bats.

The first baseman fits the profile of the prototypical first baseman. He hits for power and plays some of the best defense at the position in the minor leagues. Bellinger has continued to become a better hitter as he’s gotten older, and as he’s progressed through the minors. He continues to trend in the right direction, and the 22-year-old will likely get a taste of big league pitching this season. Bellinger has also played in the outfield, and he likely will come up in left field or right field initially. Gonzalez still has two years left on his expensive deal, and he will likely remain a Dodger through the 2018 season at least. Regardless of where Bellinger plays, his bat will produce.

Gleyber Torres, SS, New York Yankees

Gleyber Torres has been skyrocketing up all prospect lists over the last couple of years, and rightfully so. The 20-year-old signed with the Chicago Cubs as an international free agent in 2013, and the hype started almost immediately.

Torres made his debut in 2014 and hit .297/.386/.440 with two home runs in 50 games at the Rookie/Single-A levels as a 17-year-old. 2015 saw Torres hit .287/.346/.376 with three homers in 126 games in Single-A. He hadn’t shown the power that scouts expected him to develop, but that changed in 2016. That year, Torres hit .270/.354/.421 with 11 HR and 21 SB in 125 games in Single-A.

Torres is yet to play a game above Single-A, but the tools and talent are real. The Yankees acquired him from the Cubs last season in the Aroldis Chapman trade, and he is the prized possession of the Yankees’ rebuild. Torres was the Cubs’ 23rd-ranked prospect by Baseball America after the 2013 season, and he has steadily climbed to the point he’s at today. The shortstop is ranked third on the MLB Pipeline list of baseball’s top 100 prospects, and he ranks fifth on the same list for Baseball America.

Torres is probably still a year away from the majors, but when he gets there, you can bet he’ll be playing shortstop everyday for the Bronx Bombers. Torres rates as a plus-defender with a plus-arm, and above average hit tools. The Yankees believe they have their heir apparent to Derek Jeter (sorry, Didi Gregorius), and he’s done nothing to indicate that they aren’t right in that summation.

Kyle Tucker, OF, Houston Astros

Kyle Tucker is still just scratching the proverbial surface. The 20-year-old product of the legendary Plant High School in Tampa, Florida, was selected with the fifth pick in the 2015 Draft. He got his feet wet in Rookie-ball that year, but he hit just .246/.294/.353 with three homers and 18 SB. Last season, Tucker displayed some of the plus-tools he was believed to have when he was drafted by the Houston Astros. In 2016, Tucker hit .285/.360/.438 with nine home runs, 69 RBI and 32 SB in Single-A. Tucker has shown terrific plate discipline, and the power/speed combination that he showed last year is expected to aid the beginning of Tucker’s ascension through the minor leagues.

Tucker will likely make what is believed to be the biggest jump in the minors this year, which is from Single-A to Double-A. Regardless of how he performs there, he will likely spend much of the year at that level honing his skills. Tucker is on track to possibly make his big league debut in 2018, and the Astros are confident they have yet another budding, young star in the outfielder. He has the potential to be a top-of-the order hitter with 20/20 potential with some good on base capability.

Three Down - Falling Prospects

Carson Fulmer, RHP, Chicago White Sox

Carson Fulmer’s rise through the minor leagues was akin to that smart kid in your class who skipped a grade. The comparisons between Fulmer and that baby genius end there. That child probably went on to dominate the fifth grade, but Fulmer didn’t enjoy that same success in the big leagues.

Fulmer was selected eighth overall in the 2015 Draft, and it was expected that the White Sox were going to move him up through their system quickly; that they did. Palmer dominated Rookie-ball and Single-A in 2015, with a 1.96 ERA and 1.13 WHIP in 23 innings. He also had a 26/9 K/BB ratio. Despite the dominance, the walks were a bit of a concern. Fulmer pitched in Double-A and Triple-A in 2016, but he also got the call to the show just a year after being drafted. Fulmer struggled at all three levels he pitched in last season. In the minors, all 21 of his appearances were starts, and he was 6-10 with a 4.63 ERA and 1.48 WHIP. He had a 104/56 K/BB ratio in 103 innings. In the major leagues, all eight of Fulmer’s games were out of the ‘pen. In 11 2/3 innings, the righty allowed 11 runs and had a 10/7 K/BB ratio.

Fulmer doesn’t throw hard enough to get by with such alarming BB-rates. He has a 4.64 BB/9 IP in 126 career minor league innings, and that total was 5.40 BB/9 IP in his brief taste of big league action last year. Fulmer stands “just” 6-feet tall, and that has had some scouts concerned about the downward trajectory he’d be able to get on his pitches. With his struggles in 2016, those concerns seem very real now. Fulmer will likely end up in a relief role in the big leagues, hurting his fantasy stock immensely. With the trades the White Sox made this offseason- acquiring the likes of Michael Kopech, Lucas Giolito, Reynaldo Lopez and even Dane Dunning- Fulmer’s stock in the White Sox’ farm system is starting to plummet quickly.

Robert Stephenson, RHP, Cincinnati Reds

Robert Stephenson was drafted in the first round way back in 2011. He turns 24 years old in the next couple of days, and the Reds are hoping that he’s able to contribute this season. Stephenson was progressing nicely through the lower levels of the minors, but his development has hit a snag in the higher levels.

In Rookie-ball and in Single-A in 2012, Stephenson had a 72/23 K/BB ratio in 65 innings, with a 3.18 ERA and 1.18 WHIP. In 2013, Stephenson was very impressive in Single-A, with a 2.67 ERA in 97 2/3 innings at that level. That year, he got a taste of Double-A ball, and started to show his first signs of trouble. In four starts there, he had a 4.86 ERA and 13 BB in 16 2/3 innings. 2014 was Stephenson’s first full year at the Double-A level, and he struggled once again. He had a 4.76 ERA and a 4.87 BB/9 IP in 136 2/3 innings. Despite the struggles, he saw time in both Double-A and Triple-A in 2015. His walk rate was once again an alarming 4.70 BB/9 IP, which led to a 3.83 ERA and 1.30 WHIP. Last season was another one to forget for Robert Stephenson. He bounced back and forth between Triple-A and the big leagues, and he had a 4.41 ERA and 1.36 WHIP in 136 2/3 innings. That came with a 4.68 BB/9 IP and his K-rate dropped to a career-low 7.90 K/9 IP. In his eight big league starts in 2016, Stephenson had a 31/19 K/BB ratio in 37 inning, and had a 6.08 ERA.

Stephenson is expected to be a part of the Reds’ rotation this season, but if his control issues and struggles in the higher levels of the minors and in the major leagues are any indication, he likely won’t provide much value. His stock is on the way down, and at this rate, his only future (if any) in the big leagues, appears to be as a relief pitcher.

Forrest Wall, 2B, Colorado Rockies

Forrest Wall was on almost every top-100 prospect list just a year ago, but his stock has experienced a big drop. The second baseman spent all of 2016 in High-A, and he disappointed with a .264/.329/.355 slash-line, with just six homers (26 extra-base hits) and 22 SB. That came after he hit .286/.366/.439 in Single-A in 2015. Wall has seen his BB-rate fall every season, and has had a corresponding increase in K-rate every season as well. He hasn’t played a day above Single-A yet and the struggles have already started. The 21-year-old is still young enough to put everything together and realize his true potential. A big plus for Wall is that his left-handed bat has shown a fair bit of competence against left-handed pitchers, and his defense appears to be good enough to play at the highest level. The minor leagues are not littered with stud second base prospects, so the Rockies could be patient enough with Wall to give him a couple of years to develop. That said, his value as it stands today is considerably lower than what it was just a year ago.