As a 1997 graduate of Red River High School, was a multisport standout who made his mark on the basketball court and baseball diamond before going on to a professional career in scouting. As a three-year varsity basketball letterwinner and starter, Mahoney earned All-EDC honors in 1997 as a dynamic guard. On the baseball field, he was a key contributor for the Grand Forks Royals American Legion team in both 1996 and 1997, helping lead them to back-to-back state runner-up finishes. Though individual awards were not given for Legion baseball, Mahoney's impact was undeniable; he recorded 19 pitching wins and 185 strikeouts over two seasons. Mahoney continued his baseball career at the University of North Dakota, where he emerged as one of the nation’s top Division II pitchers. In 1999, he earned All-North Central Conference and All-Central Region honors, and finished second in the nation in strikeouts per nine innings. In 2000, he was drafted by the Milwaukee Brewers as a pitcher. Following his playing career, Mahoney transitioned into scouting and has since built a highly successful 20-year career as a Major League Baseball scout, working for both the Boston Red Sox, with whom he was part of three World Series championships, and the New York Mets.