Conner Penfold/Giant Potential

Conner Penfold/Giant Potential

16. Jordan Johnson

Jordan Johnson went from 23rd rounder to Top-20 prospect with one breakout half season. Johnson, a native of Elk Grove, Calif. who went to Franklin High School and California State Northridge, began the 2015 season late in rookie ball while building strength back up from a minor tear in his lat muscle. He joined the San Jose Giants, jumping over Class-A Augusta, in early August where he made six starts and was crucial for the team in the rotation during their playoff run. Johnson ended the regular season with a 4.2 inning, 10 strikeout performance that opened many eyes. Johnson features a low-to-mid 90s four-seam fastball with moderate running action, a 12-6 curveball, a circle-changeup, and is currently in the process of adding a two-seam fastball.

2016 Stats // VIDEO // ETA: 2019

Conner Penfold/Giant Potential

Conner Penfold/Giant Potential

17. Michael Santos

Michael Santos was the second youngest player on the list until newcomers Lucius Fox and Jalen Miller, his new teammates, joined the organization. The 20-year-old Dominican could follow on fellow countryman Joan Gregorio by adding some weight to bolster his already solid stuff. He uses a low-90s fastball with tail, a changeup, and his plus curveball. That thing is big. Santos opened eyes in the Arizona League in 2014, starting 12 games and reaching his five-inning pitch limit 11 times. He also finished fourth in the league in ERA and innings pitched. He pitched in Augusta in 2015, but missed most of the first three months with an arm injury. He returned in July, posting a 3.44 ERA the rest of the way. Sent back to Augusta for 2016, he should find himself in San Jose by season's end.

2016 Stats // VIDEO // ETA: 2019

Tim Cattera/MiLB.com

Tim Cattera/MiLB.com

18. Aramis Garcia

San Francisco has Buster Posey and Andrew Susac, and yet they still snagged Aramis Garcia in 2014's second round. That should say something about this Conference USA Player of the Year. Garcia struggled in 2014 in his first professional stint, splitting time between rookie ball and Salem-Keizer, and improved a bit in 2015. He clubbed 15 home runs and 15 doubles, slugging .467 for the GreenJackets. This offensive-upsided catcher shows good plate discipline and tracking of pitches, and displays pop times around two seconds from behind the dish. Everything defensively about Garcia appears average at best, and because of that, it will certainly be his bat speed and raw power that potentially propel him to the major leagues as a likely backup catcher.

2016 Stats // VIDEO // ETA: 2018