Edit: The folks at SoxProspects have revised their list of players who are eligible for the Rule 5 draft, based on a minor shift in the rules. Navarro (along with several other Red Sox players) is now longer eligible, so he won't need to be on the 40 man roster. Enjoy the now mostly irrelevant write up on Navarro or consider it a preview of the shortstop state of the system.
As a follow up to the post on Robert Manuel, I thought I would take a look at the Red Sox prospects who are eligible for the Rule 5 draft. This is not a definitive list, as to the best of my knowledge the Sox can still move players on and off the 40 man roster to address eligible players. In order to be eligible to be drafted a player must not be on the 40 man roster and must either: spent 4 years in the minors if signed at 18 or older or have spent 5 years in the minors if signed younger than 18. The drafting team pays $40,000 to the team who initially had the prospect's rights. In order for the drafting team to keep the prospect, the player must remain on the major league (25 man) roster for the entire season. If the player is removed from the 25 man roster, then the drafting team must offer the player back to the original team for $20,000.
Most rule 5 draftees don't amount to anything, and many are returned to their original teams before the end of spring training. There are some notable exceptions: Johan Santana is easily the best player drafted in the last 10 years, although the Marlins struck gold with Dan Uggla as well. Because of the rules and requirements associated with the draft, many teams don't draft anyone. Last year no one from the Red Sox system was drafted, and the Red Sox drafted Miguel Gonzalez, who spent the entire season the DL rehabbing from Tommy John surgery.
Looking over the list of eligible players for the draft, the only name that really jumps out at me is Yamaico Navarro, who is the best upper level shortstop prospect in the system. Navarro is a 21 year old shortstop from the Dominican Republic; because he is eligible for the draft at such a young age he must have been a 16 year old signing for the Red Sox. His performances in the minor leagues have been uneven. In several seasons he has excelled at one level (>.900 OPS), only to struggle at a higher level (<.600 OPS). In fact, his last 5 year/league splits have either been in the .500s or .900s. When hitting well, Navarro does a bit of everything. At his best moments he's posted a slugging percentage over .500, which is very impressive for a shortstop. Even when he doesn't hit well, Navarro has shown a good batting eye. According to SoxProspects, Navarro is a good fielder and is likely able to stick at shortstop.
Because of his struggles at AA I wouldn't expect him to be picked, but thanks to the open spots on the Red Sox roster, it simply isn't worth the risk. Because Navarro is young and and a promising all around shortstop, it is conceivable a team would pick him in hopes of stashing him on the major league roster for a year, then send him down to the minors for more seasoning after 2010.