As a junior, Merrill averaged 18.3 points, 6.8 rebounds, 5.4 assists, and 2.2 steals per game and was named first-team all-state by the Deseret News and Salt Lake Tribune.

He posted 15.8 points, 7.4 assists, 4.6 rebounds, and 2.3 steals per game as a senior and led Bountiful to a 4A state title.

[1] Merrill went on a two-year mission for the Church of Jesus Christ of Latter-day Saints to Nicaragua before his freshman year at USU.

He was named the MWC Player of the Year and tournament MVP, as well as AP Honorable Mention All-American.

[4] Merrill had a career-high 38 points on March 5, 2019, in a 100–96 overtime victory over Colorado State University (CSU).

[3] In the season opener of his senior year, Merrill had 28 points to help USU defeat Montana State 81–73.

[5] On February 11, versus CSU, Merrill eclipsed the 2,000-point mark for his career and passed Wayne Estes for third on USU's all-time scoring list.

[9] On November 18, 2020, Merrill was selected by the New Orleans Pelicans as the final pick of the 2020 NBA draft.

On August 7, 2021, Merrill was traded, along with two future second-round picks, to the Memphis Grizzlies in exchange for Grayson Allen.

[18] On December 20, he scored a career-high 27 points and hit 8 three-pointers off the bench as the Cleveland Cavaliers beat the Utah Jazz 124–116.