Prior to joining the Washington Nationals, Jageler was the voice of International League Triple A Pawtucket Red Sox for the 2005 season. He has also called baseball games for the Charlotte Knights and Syracuse Chiefs. Pawtucket is noted as being a springboard for Major League baseball broadcasters. Jageler joins former Pawtucket announcers Gary Cohen (New York Mets), Don Orsillo (Boston Red Sox), Dave Flemming (San Francisco Giants), Andy Freed (Tampa Bay Devil Rays) and Aaron Goldsmith (Seattle Mariners) in the Majors. Before working as a full-time baseball announcer, Jageler worked in Boston and Charlotte, North Carolina as a sportscaster, co-hosting talk shows and doing play by play of various sports, including fill-in work on the Boston Celtics radio network and serving as the team's PA announcer during part of the 2002–03 NBA season. While in Charlotte he was the voice of Collegiate Division I Charlotte 49ers (University of North Carolina at Charlotte) basketball team.
Jageler called every Nationals regular-season game from Opening Day in 2006 – his first as a Nationals broadcaster – until May 31, 2018, when he finally missed a game to attend his son′s high school graduation. His Nationals broadcasting streak ended at 2,016 consecutive games. Longtime Harrisburg Senators broadcaster Terry Byrom took his place for four games from May 31 through June 3, 2018. Jageler returned to the booth on June 5, 2018.
- Janes, Chelsea (June 4, 2018). "After 2,016 straight games, Nationals broadcaster ends his iron-man streak". Washington Post. Retrieved May 12, 2019.
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