He will play LF, 1B and 3B at AAA Las Vegas because "the Dodgers consider him the hitting prospect they would call up first if there were a long-term need at those positions."
I have some quibbles with the use of the plural of "position".
I do wonder what "lomg-term" need means. The rest of this decade or for an extended period of time during the 2006 season?
If it is the latter, then do not get ready to activate him from your reserves at the initial DL-ing of Nomar, Mueller or Drew.