[9] He officiated his first match in Poland's top professional league in 2009 at the GIEKSA Arena, in a game between GKS Bełchatów and Odra Wodzisław Śląski.

[13] The same year, he also debuted as a referee in the Europa League in the qualifying match between Aalesunds FK and Ferencvárosi TC.

[15] He refereed at 2014 FIFA World Cup qualifiers,[16] beginning with the Group F match between Portugal and Azerbaijan.

[20] He participated in the UEFA Euro 2016 and refereed three matches: Spain-Czech Republic and Iceland-Austria in the group stage of the tournament as well as Germany-Slovakia in the knockout phase.

[25] On 15 December 2022, it was announced that he would officiate the World Cup final between Argentina and France, becoming the first Polish referee to do so.

[26][27][28] His performance in the final was highly praised by many commentators as well as fellow referees including Pierluigi Collina, Howard Webb, Keith Hackett, Lutz Wagner[29][30] and Thorsten Kinhöfer.

[31] On 17 May 2023, he refereed the UEFA Champions League semi-final match between Manchester City and Real Madrid (4–0).

[35] On 22 December 2023, Marciniak took charge of the 2023 FIFA Club World Cup Final in Jeddah between Manchester City and Fluminense FC.

[38] On 1 June 2023, it was reported that three days earlier Marciniak spoke at an entrepreneur conference co-organised by Sławomir Mentzen, a right-wing libertarian politician and leader of the Confederation Liberty and Independence in Poland, who has in the past been accused of anti-semitic and anti-LGBT statements.

[40] Marciniak responded to Never Again's report by releasing a statement in which he dissociated himself from the views presented by the organizer stressing that he "always puts fair play and respect for other people first".