The Yankees have added left-handed pitcher Wilkin De La Rosa and right-hander Eric Hacker to the 40-man roster.Adding people to the 40-man in a case like this is done to protect them from the Rule 5 draft.
De La Rosa, 23, was 9-4 with a 2.11 ERA in 32 combined games (11 starts) with Class A Charleston and Class A Tampa in 2008, ranking fifth in the organization in strikeouts (125 in 106 2/3 innings). De La Rosa was originally signed as an outfielder and converted in 2007.
Hacker, 25, was 9-6 with a 2.43 ERA in 26 combined starts with Class A Tampa and Double-A Trenton in 2008, ranking second in the organization in ERA. He was the Yankees' 23rd-round pick in 2002.
Here are the MiLB.com player pages for both Hacker and De La Rosa.