Miguel Sano got a lot of the praise following his breakout rookie performance in 2015. He finished in third place in the American League Rookie of the Year voting and he was named the Twins Most Valuable Player even though he played in less than half of the team's games. He made a tremendous impact but he wasn't the only rookie leaving his mark at the big league level.
Eddie Rosario made his debut on May 6, 2015 and spent the rest of the season in the Twins outfield. The former fourth round pick would go on to lead all of baseball with 15 triples and he lead the American League with 12 outfield assists. He became the 18th rookie since 1901 to reach double digits in homers, triples, doubles, and stolen bases. Also, he's on the ninth player in Twins history to record at least ten homers and ten triples in a season.
Rosario's career in the minor leagues might best be described as tumultuous. He burst onto the scene in 2011 by winning the Appalachian League MVP and out homering Miguel Sano and Kennys Vargas. Over the next two seasons, the routine became double-digits in home runs and over 30 doubles. The Twins thought so highly of Rosario, they transitioned him to second base, a position of need in the organization at the time.
During the 2014 off-season, the hammer fell on Rosario. He was handed a 50-game suspension for a second violation of the Minor League Drug Prevention and Treatment Program. After returning from the suspension, Rosario hit poorly for the first time in his professional career. The Twins sent him back for a second stint in the Arizona Fall League where his bat started to show some signs of life.
Flash-forward to 2015 and Rosario wasn't exactly hitting the cover off the ball when he was called up from Rochester. Through 23 games, he was batting .242/.280/.379 with six extra-base hits. His batting average was almost 50 points lower than his career in the minor leagues and he was getting on base 6% less than his career average.
Now, it's weeks away from Rosario reporting to his first spring training where he will enter the year with his name already penciled into a starting job. Some players run into struggles during their second full season at the big league level. There are more advanced scouting reports on players so pitchers have a better idea how to attack a batter. This is where the term "sophomore slump" has been used in baseball circles.
Will Rosario be able to breakthrough the sophomore slump and actually be a sophomore stud?
Baseball Reference projects Rosario to hit double digits in home runs, triples, and doubles while increasing his batting average and on-base percentage. FanGraphs ZiPS projects have Rosario's batting average dropping over 10 points and his on-base percentage staying around the same point. They also have him combining for 44 extra-base hits which would be two less than the 2015 season in over 50 more plate appearances.
After the numbers Rosario put together in his rookie season, it is going to be tough to live up to the offensive punch he provided. However, there are some adjustments he can make to avoid slumping in 2016. In every minor league season before his second drug suspension, Rosario got on base over 34% of the time. He also struck out in 19% of his at-bats compared to 26% in his rookie season. If Rosario could improve his walk rate and reduce his strikeout percentage, he might be able to avoid some of the biggest parts of the sophomore slump.
One of the things working in Rosario's favor has been the fact that he's hit tool was always considered advanced in the minor leagues. His quick wrists and good plate coverage meant that his bat looked MLB ready even if other parts of his game weren't there yet. Because of this advanced approach, Rosario should be able to avoid any long-term slumps at the big league level.
Some minor tweaks here and there should make Rosario a solid contributor in his sophomore season and he could surprise a lot of people with his performance.