Merkulov committed to play college ice hockey for the Ohio State University during the 2021–22 season. In his freshman year, he led all NCAA freshmen with 20 goals, and was named to the All-Big Ten Freshman Team and the All-Big Ten First Team.
On 9 April 2022, Merkulov concluded his collegiate career after he was signed to a three-year, entry-level contract with the Boston Bruins, and was assigned to their AHL affiliate, the Providence Bruins, where he would play for the remainder of the season.