Rzonca was born in Leeds, West Yorkshire, and started his career with the youth systems of Huddersfield Town and Barnsley.[2] He started an apprenticeship with York City in 2013, and signed a one-year professional contract with the club in May 2015.[4][5] Rzonca made his first-team debut on 25 August 2015 as a 71st-minute substitute for Vadaine Oliver in York's 3–0 away defeat to Premier League team Swansea City in the League Cup second round.[6] He joined Northern Premier League Premier Division club Stamford on 15 March 2016 on a one-month loan,[7] making his debut the same day as a 75th-minute substitute in a 4–1 home defeat to Darlington 1883.[8] Rzonca made nine appearances[8] as Stamford were relegated in 21st place in the Northern Premier League Premier Division.[9] He finished the 2015–16 season with two appearances for York,[6] as they were relegated into the National League in 24th place in League Two.[10] He signed a new one-year contract in June 2016.[11]
Rzonca joined National League North club Harrogate Town on 20 January 2017 on a one-month loan.[12] He made his debut on 28 January 2017 as a 71st-minute substitute in a 3–1 home defeat to Gainsborough Trinity.[13] This was Rzonca's only appearance for Harrogate[13] before returning to York.[14] He was released by York at the end of 2016–17.[15]
Later career
Rzonca signed for newly relegated National League North club North Ferriby United on 28 July 2017 after a successful trial.[16] In January 2018, Rzonca joined Polish side Zagłębie Sosnowiec and was part of the side which achieved promotion to the Ekstraklasa.[17] On 22 January 2019, after a year with Zagłębie, he joined I liga side GKS Katowice on a deal until the end of the season with the option of an additional year.[18] He left the club at the end of the season.[19]