Prior to entering his freshman year at South Dakota State University, Emery was ranked the top 2010 draft prospect in the Dakotas by Baseball America. Last summer Emery played American Legion baseball with Rapid City (S.D.) Post 22 where he hit for a .450 average in 62 games while leading his state championship team with 99 hits, 23 doubles, four triples, 11 home runs, 78 runs batted in and 163 total bases. Emery also led the way on the mound for Post 22 posting a 10-2 record and a 2.17 ERA which included a three-hitter to win the state championship. He finished the summer season with nine complete games, including three shutouts, and struck out 108 opposing batters.

Emery was named the 2009 South Dakota American Legion Player of the Year after excelling both at the plate and on the mound for Rapid City Post 22. He hit .410 with a team-leading five home runs and also led the team with a 2.18 ERA in 86 innings pitching, recording 100 strikeouts against only 18 walks.