Hale, 22, hit .327 with four home runs and 56 RBIs during his senior season for a Tigers team that swept its regional and a super regional against Louisiana-Lafayette on its way to the College World Series. LSU's run ended at the hands of TCU in Omaha on Thursday.
Warren, from Napoleon, Ohio, started 12 games for Division II Ashland in 2015, finishing his junior season with a 5-4 record and a 3.88 ERA.
James worked mostly as a reliever for the Cardinal, earning a 2-4 record and posting a 4.75 ERA in 17 appearances in 2015, 15 of them coming out of the bullpen.