Hillaert was drafted in the 5th round (165th overall) of the 1999 MLB Player Draft by the Texas Rangers. The RHP played several years in the Rangers organization, including his best season in 2002, when he posted a 3.27 ERA in 55 innings. He threw in 32 games that season and struck out 65 hitters for a 10.6 strikeout-per-game ratio. Hillaert was a power pitcher and had a blazing fastball that reached into the mid-90s.
Hillaert is a native of Langhorne, Pa., and he played collegiately at Shippensburg University. He founded High Heat Baseball Club in 2001 in Michigan and moved the organization to Salisbury, Md., in 2006. In 2010, Hillaert became an MLB Scout with the Milwaukee Brewers and he served as an assistant coach with University of Maryland Eastern Shore for several years.