Jill is an explosive American outside hitter known for her relentless energy, powerful offense, and all-around skill. A standout at the University of Arkansas, Gillen was a four-time All-SEC selection, a 2023 AVCA Second Team All-American, and finished her collegiate career as the Razorbacks’ all-time leader in service aces (189) and second in career kills (2,075). She helped propel Arkansas to multiple NCAA Tournament appearances and earned five SEC Player of the Week honors throughout her time in Fayetteville. Professionally, Gillen was selected 8th overall in the 2023 PVF Draft by the Omaha Supernovas before being traded to the Orlando Valkyries, later joining the Columbus Fury for her second pro season. Now heading to Europe, she is signed with Swiss powerhouse Sm’Aesch Pfeffingen for the 2025–26 season, continuing her upward trajectory on the international volleyball scene.