On September 6, 2019, Petrov made his home collegiate debut for Holy Cross against UMass Lowell, scoring his first collegiate goal. During the remaining 2019 NCAA Division I men's soccer season, Petrov recorded 17 appearances and 5 starts, scoring 3 goals against UMass Lowell (American East Conference), Rhode Island (Atlantic 10 Conference), and Lehigh (Patriot League Conference). Petrov was recognized in the New England Soccer Journal as a freshman standout and was named to the All-Patriot League Men's Soccer Academic Honor Roll. After entering the NCAA transfer portal in November 2019, Petrov committed to continuing his collegiate career in the Big West Conference with UC Santa Barbara - a nationally top-ranked NCAA Division I men's soccer program.