With the 2019 Minor League Baseball season getting underway, here's a look at where the Mariners' 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. Justus Sheffield (MLB No. 42), LHP -- Tacoma Rainiers (AAA)
2. Jarred Kelenic (MLB No. 55), OF -- West Virginia Power (A)
3. Justin Dunn (MLB No. 89), RHP -- Arkansas Travelers (AA)
4. Evan White, 1B -- Arkansas Travelers (AA)
5. Julio Rodriguez, OF -- West Virginia Power (A)
6. Logan Gilbert, RHP -- West Virginia Power (A)
7. Kyle Lewis, OF -- Arkansas Travelers (AA)
8. Sam Carlson, RHP -- Extended spring training -- rehab
9. Erik Swanson, RHP -- Tacoma Rainiers (AAA)
10. Noelvi Marte, SS -- Dominican Summer League
11. Braden Bishop, OF -- Tacoma Rainiers (AAA)
12. Shed Long, 2B -- Tacoma Rainiers (AAA)
13. Cal Raleigh, C -- Modesto Nuts (A Adv)
14. Jake Fraley, OF -- Arkansas Travelers (AA)
15. Dom Thompson-Williams, OF -- Arkansas Travelers (AA)
16. Wyatt Mills, RHP -- Arkansas Travelers (AA)
17. Matthew Festa, RHP -- Seattle Mariners (MLB)
18. Joey Curletta, 1B -- Tacoma Rainiers (AAA)
19. Juan Querecuto, SS -- Extended spring training -- rehab
20. Joey Gerber, RHP -- Modesto Nuts (A Adv)
21. Art Warren, RHP -- Arkansas Travelers (AA)
22. Brayan Perez, LHP -- Extended spring training
23. Joe Rizzo, 3B -- Modesto Nuts (A Adv)
24. Nick Rumbelow, RHP -- Seattle Mariners (MLB)
25. David McKay, RHP -- Tacoma Rainiers (AAA)
26. Ricardo Sanchez, LHP -- Arkansas Travelers (AA)
27. Gerson Bautista, RHP -- Seattle Mariners (MLB) -- IL
28. Nolan Hoffman, RHP -- West Virginia Power (A)
29. Keegan McGovern, OF -- Extended spring training -- rehab
30. Donnie Walton, 2B -- Arkansas Travelers (AA)
    Complete list »

On the shelf
A gruesome knee injury suffered during his debut summer has kept the 2016 first-round pick from truly showing who he is as a player, and he’s played in just 165 games as a pro since being drafted. The good news is he’s healthy and if his .423/.464/.923 line in 26 Cactus League at-bats is any indication, he’s ready to finally put the injury behind him.

Impact prospect: Justus Sheffield
While he didn’t get a ton of innings this spring, Sheffield made a lasting impression in big league camp with his new organization. Part of the James Paxton return from the Yankees, the confident lefty will work to refine things in Triple-A knowing he has the chance to spend most of the 2019 season in Seattle.

Breakout prospect: Julio Rodriguez
Rodriguez, signed for $1.75 million in July 2017, hasn’t even played a game in the United States yet, but the Mariners have trouble containing their excitement about Rodriguez. He showed up to camp this spring in phenomenal shape and has wowed with his makeup as much as his tools. He has the chance to develop into one of the best offensive prospects in baseball.

Best defensive prospect: Evan White
It's not often a first baseman is mentioned as one of the premier defensive players in the Minors, but that's the reality with White, who recently was named to the All-Defense Team. All signs point to him becoming a Gold Glove Award winner at the position, as he's athletic with outstanding footwork, a strong arm and plus range. His ability to pick throws is elite, and he makes every infielder on his team better as a result.