Petro joined
Big Bullets in 2018, initially playing with their reserve squad in the second-tier Southern Region Football League before being promoted to the first team ahead of the
2019 season, making an instant impact and playing an instrumental role in their second consecutive
Super League championship win. For his performance filling in the gap left by injured team captain John Lanjesi, he was named Defender of the Year while also being nominated for the Player of the Year award at the annual league awards ceremony. After rejecting a trial with South African side
Polokwane City, Petro instead underwent a month-long trial at Moldovan side
Sheriff Tiraspol in early 2020. On 7 March 2023, Petro signed with Romanian
Liga I club
Botoșani on a two-year deal. At the time, he was one of only two Malawian footballers playing in Europe, along with
Kieran Ngwenya. Petro made his debut for Botoșani in a 1–1 league draw against
Mioveni on 10 March. ==International career==