2025: Harrison played six AVP tournaments, placing fifth twice with Avery Drost, including in Manhattan Beach. He played four times with Charlie Siragusa with a best of a third on the Tour Series and a fifth in both a Tour Series and a Heritage Series event. Harrison and Drost competed for the Austin Aces in the AVP League, finishing with an 0-8 match record. The duo placed third in a World Series Futures event, then Harrison and Cody Caldwell played in five World Tour tournaments with a best of ninth in a Challenge event. Harrison and Drost placed fourth in their only NORCECA tournament.

2024: Harrison began the season with a qualifier loss alongside David Wieczorek, then played four AVP tournaments with Brian Miller. The duo had a best of third on the Tour Series to go with a ninth and 13th on the Heritage Series. Internationally Harrison played four World Tour events with three different partners, losing in the qualifier each time. He won four medals in four NORCECA tournaments, winning two silvers and a bronze with Evan Cory and a gold with Jake Urrutia.

2023: Harrison played seven AVP events with six different partners with a best of 13th four times. One of those 13th-place finishes came with Cash Adamsen in Manhattan Beach after advancing from the qualifier. He also played two World Tour events including finishing fifth in a Futures event with Charlie Siragusa. 

2022: Harrison played five AVP events beginning with three qualifier losses in Tour Series events with Bryce Mayer. He then placed 17th in Manhattan Beach with Charlie Siragusa, and got his first AVP main draw match win over Phil Dalhausser. Harrison ended the year advancing from a Tour Series qualifier with Kacey Losik and placing 13th.

2021: Did not compete.

2020: Did not compete.

2019: Harrison played three AVP tournaments with three different partners. He twice lost in the qualifier but in Hermosa Beach Harrison and Kacey Losik advanced from the qualifier as the 28th seed to place 17th.

2018: Harrison lost in a pair for qualifiers with Chicory Roth.

2017: At the age of 18 Harrison played his first AVP tournament, losing in the Manhattan Beach qualifier with Kacey Losik.

College: Harrison played volleyball at UC-San Diego, where he was second on the team in both kills and points as a freshman. He led the team his sophomore season in kills, points and aces. As a junior he led his conference in aces and was 26th nationally, and was second on the team in kills and points. Harrison missed the majority of his senior season due to injury. He left the school ranked ninth in career service aces (64).

Personal: Harrison's father, Todd, played volleyball at Hawai'i and then played semiprofessional volleyball in Switzerland. His mother, Anne, went to UC-San Diego. Harrison has one older brother, Kai, and one younger brother, Noa. He went to high school in Hawai'i for two years before moving to Santa Cruz and finishing high school there. According to MaxPreps he was the national leader in kills, and he also competed in soccer, Cross country and tennis.