What is Tommy La Stella's fantasy value?

Fantasy owners had seemed awfully excited lately about a possible promotion for Atlanta Braves second base prospect Tommy La Stella, and thus there was a palpable buzz on Twitter when this actually occurred Wednesday. La Stella, a patient left-handed hitter with outstanding plate discipline, made his big league debut for the Braves in a 4-0 loss at Fenway Park, contributing a pair of well-placed, ground ball singles to center field in four at-bats. He did not homer, nor did he steal a base.