With the 2019 Minor League Baseball season getting underway, here's a look at where the O's Top 30 prospects are starting the year. We also identify the prospect who just missed the Top 30 list, a player who didn't make the big league Opening Day roster but should make an impact this year, a prospect who is ready to break out in 2019 and the team's best defensive prospect.

1. Yusniel Diaz (MLB No. 63), OF -- Bowie Baysox (AA)
2. Ryan Mountcastle (MLB No. 70), 3B -- Norfolk Tides (AAA)
3. D.L. Hall (MLB No. 88), LHP -- Frederick Keys (A Adv)
4. Austin Hays, OF -- Extended spring training (thumb)
5. Grayson Rodriguez, RHP -- Delmarva Shorebirds (A)
6. Keegan Akin, LHP -- Norfolk Tides (AAA)
7. Ryan McKenna, OF -- Bowie Baysox (AA)
8. Zac Lowther, LHP -- Bowie Baysox (AA)
9. Dean Kremer, RHP -- Extended spring training (oblique)
10. Blaine Knight, RHP -- Delmarva Shorebirds (A)
11. Brenan Hanifee, RHP -- Frederick Keys (A Adv)
12. Hunter Harvey, RHP -- Bowie Baysox (AA)
13. Jean Carlos Encarnacion, 3B -- Delmarva Shorebirds (A)
14. Adam Hall, SS -- Delmarva Shorebirds (A)
15. Richie Martin, SS -- Baltimore Orioles (MLB)
16. D.J. Stewart, OF -- Norfolk Tides (AAA)
17. Cadyn Grenier, SS -- Delmarva Shorebirds (A)
18. Dillon Tate, RHP -- Bowie Baysox (AA)
19. Luis Ortiz, RHP -- Norfolk Tides (AAA)
20. Zach Pop, RHP -- Bowie Baysox (AA)
21. Cody Carroll, RHP -- Extended spring training
22. Branden Kline, RHP -- Norfolk Tides (AAA)
23. Rylan Bannon, 2B -- Bowie Baysox (AA)
24. Jean Carmona, SS -- Extended spring training
25. Drew Jackson, 2b -- Baltimore Orioles (MLB)
26. Brett Cumberland, C -- Extended spring training
27. Mike Baumann, RHP -- Frederick Keys (A Adv)
28. Alex Wells, LHP -- Extended spring training
29. Drew Rom, LHP -- Delmarva Shorebirds (A)
30. Robert Neustrom, OF -- Delmarva Shorebirds (A)
    Complete list »

Just missed the Top 30: Lamar Sparks
The 2017 fifth-rounder sustained a torn right labrum last spring that wiped out his entire season, and it is yet to be seen how the injury has affected what once was plus arm strength. He had a promising pro debut after signing, posting a .703 OPS with 11 steals in the Rookie-level Gulf Coast League, and he still has time on his side because he’ll play all of 2019 at age 20.

On the shelf
Hays had a good spring, hitting .351 with five homers and 13 RBIs in 12 games, but he’ll start the season in extended spring training recovering from the left thumb sprain he suffered in late March. Kremer, last year’s Minor League strikeout king, was limited for most of the spring by a left oblique injury, but he resumed a throwing program in early March and is currently building up strength ahead of an eventual assignment. The Orioles will also hold back Carroll, who’s been dealing with a sore lower back, as well as Carmona, Cumberland and Wells for undisclosed reasons.

Impact prospect: Yusniel Diaz
Baltimore’s key acquisition in the five-prospect package they netted in last summer’s Manny Machado trade, Diaz shows flashes of becoming a five-tool player but stands out the most for his advanced approach and natural hitting ability. Getting him to unlock his power is the next step, and the hope is that he’ll make progress on that front in the Minors before his likely big league debut sometime during the second half.

Breakout prospect: Adam Hall
Hall might have been the most improved prospect in Baltimore’s system from start to finish in 2018. After hitting .212 during the first month of the season at Class A Short-Season Aberdeen, the 2017 second-rounder erupted to hit .358 over his final 36 games, recording a 19-game hit streak along the way. Also a plus runner who has a chance to stick at shortstop long term, he has the type of well-rounded skill set that should allow for an easy transition to full-season ball.

Best defensive prospect: Cadyn Grenier
Grenier's stellar glove work at shortstop was key in helping Oregon State win the 2018 College World Series, and in the process, he established himself as one of the best defensive prospects in the Draft before going to the Orioles as the No. 37 overall pick. With good hands, plus arm strength and plenty of range, Grenier has all the ingredients needed to stick at the position long term.