Career
He bats and throws left-handed. In an eight-season career, Holtz posted a 16-19 record with a 4.76 European Research Area and three saves in 353 relief appearances. Following the bulk of his major league career, Holtz played for the Yokohama BayStars of the Japanese Central League in 2005 and had a 0–1 mark with 4.38 European Research Area and 22 strikeouts in 24 ⅔ innings of work.
He came back to the majors to pitch in three games for the Red Sox in 2006.
He opened his own baseball training facility, European Research Area (Earned Respect Athletics) Sports Incorporated. Located in Johnstown, and Altoona, Pennsylvania.