Monday, Baseball America released their top 10 Rays prospects for 2015. If you subscribe to BA, you can get scouting reports on those players and access to Bill Ballew's chat about the system. I'll include brief thoughts about the players, but I'd recommend subscribing to get the full details.
1. SS Willy Adames (last season: DET #30)
+ Four average or better tools, bat should play even if he moves at shortstop
- Not a lock to stick at short
2. RHP Alex Colome (last season: TB #5)
+ Plus fastball, secondary pitches have potential
- Out of options, nearly as old as Brandon Guyer
3. C Justin O'Conner (last season: TB #12)
+ Could have the strongest arm behind the plate in the minors, has power potential at the plate
- Aggressive approach could limit his offensive value
4. SS Adrian Rondon (last season: not a professional player)
+ Tools draw favorable comparisons to Hanley Ramirez
- Barely 16 years old, hasn't had a professional plate appearance yet
This one I really wanted to dive in to. Rondon was BA's top international prospect for this year's signing period, but off the top of my head, I don't remember seeing a 16 year old this high in a team's top 10 before. Here are some recent top international players (according to BA) and how they fared in their first organizational rankings.
2014 #1: SS Adrian Rondon (Rays- 4th)
2014 #2: OF Juan De Leon (Yankees- out of top 10)
2014 #3: OF Brayan Hernandez (Mariners- top 10 not yet released)
2013 #1: OF Eloy Jimenez (Cubs- 16th)
2013 #2: SS Gleyber Torres (Cubs- 23rd)
2013 #3: 3B Rafael Devers (Red Sox- 20th)
2012 #1: SS Franklin Barreto (Blue Jays- not ranked)
2012 #2: C Luis Torrens (Yankees- not ranked)
2012 #3: RHP Jose Mujica (Rays- 23rd)
Prior to that, their international prospect rankings were based on projected signing bonus, not talent. BA writers aren't a monolithic block though, so maybe it's just Bill Ballew's style to rank international prospects high on his lists. Every year, he does the rankings for the Rays and Braves. Here's how he ranked the top fresh international signings each year for those teams.
2015 Rays: SS Adrian Rondon (4th)
2014 Rays: None
2013 Rays: RHP Jose Mujica (23rd)
2012 Rays: None
2011 Rays: OF Yoel Araujo (18th)
2015 Braves: Not yet released
2014 Braves: None
2013 Braves: None
2012 Braves: None
2011 Braves: SS Edward Salcedo (16th)
This isn't definitive at all for any number of reasons. The talent isn't necessarily all equal, both in terms of individual players and in the organizations. Maybe Ballew has changed his process in recent years. Whatever the reason, or combination of reasons, that results in Rondon being ranked fourth, it seems like he's in uncommon, if not unchartered, territory for a 16 year old.
Baseball America league top 20 prospect lists wrapup
5. RHP Nate Karns (last season: TB #9)
+ His fastball and breaking ball are both good pitches
- Sometimes struggles with command and can allow home runs
6. OF Mikie Mahtook (last season: TB #25)
+ Continued to show solid tools in breakout 2014 season, including improved defense in center field
- Strikeout rate jumped a bit in 2014, but it was still manageable
7. 2B Ryan Brett (last season: TB #8)
+ Has surprising power for his size, uses speed to his advantage in all facets
- Doesn't walk as much as he used to, but his strikeout rate is still roughly the same
8. RHP Brent Honeywell (last season: Walters State)
+ Throws a screwball
- Limited number of innings in pro debut
9. LHP Blake Snell (last season: TB #14)
+ Showed improved fastball velocity this year to go along with his slider
- Has to repeat his delivery and throw more strikes
10. 1B Casey Gillaspie (last season: Wichita State)
+ Switch hitter with power from both sides of the plate
- Has to stop chasing pitches out of the strike zone