Koller found pickleball in Las Vegas in 2018 after moving there for a job and began playing pro tournaments in 2019. Known for his crab walk along the kitchen line, lightning-fast hands, and lanky stature, Koller is an imposing threat at the net but also one of the best defenders in the game. He describes his game as “all wrist” and attributes his wrist strength and dexterity to his 16-year hockey career. Never spotted on-court without rolled-up sleeves and a backwards hat, Koller is a man of few words.

Koller’s self-professed favorite shot is the lob and has helped the shot gain traction and popularity— a shot he transferred over from his days on the tennis court. He began playing pickleball because he felt that he never committed himself fully to tennis. For Koller, pickleball is a way of proving what he could or couldn’t do in a racquet sport after quitting tennis after high school.

Koller grew up in St. Louis, Missouri with two sisters and spent his childhood playing hockey and tennis. He went to University of Colorado: Boulder where he played ice hockey all four years. He graduated with a degree in civil engineering and worked in construction project management for 8 years, including handiwork as part of the “Tiny House Movement.” Now, AJ is a full-time touring pro on the PPA Tour.

Koller enjoys videography, movies, carpentry, skiing, and professional sports. He admits he has an obsession with popcorn and is known to take down multiple bags in a single day.