On 3 December 2018, Brighton announced that Mandroiu had been released and had signed for League of Ireland Premier Division outfit Bohemians. He made his debut for the Gypsies on 15 February 2019 in a 1-0 home victory over Finn Harps. His first goal for the club came a week later, when he found the net away to U.C.D. in a 2-0 win. Further goals would come against Derry City and St Patrick's Athletic, with Mandroiu earning numerous plaudits for his performances. He was nominated for the SWAI Player of the Month award for both April and May, but lost out to Bohemians teammate James Talbot and Dundalk's Sean Gannon respectively. Such was his fine form in his debut season, that Bohemians announced on 19 May that the young midfielder had been given a new contract at the club. On 14 June, Mandriou scored two goals in a 2-1 Dublin Derby win over rivals Shamrock Rovers, including a game-winning strike from 30 yards out. This was followed up with an SWAI Player of the Month award for June 2019. Mandriou would go on to win PFAI Young Player of the Year, beating off fellow nominees David Parkhouse and Republic of Ireland international Jack Byrne, while he was also named in the PFAI Team of the Year. July 2020 saw Mandroiu linked with a move to Dutch Eredivisie side FC Twente.
International career
Mandroiu has represented the Republic of Ireland at under-16, under-19, and under-21 levels. He earned his first cap with the under-21s in a European Championship qualifierat home to Luxembourg, coming on as an 86th-minute replacement for Connor Ronan. The Republic of Ireland would win the game 3-0 in what was manager Stephen Kenny's first game in charge. Following this, Mandroiu was not included in Kenny's squad for the Toulon Tournament. In September2019, Mandroiu was selected by Kenny for Ireland's squad in upcoming qualifiers against Armenia and Sweden. He came on as a substitute against Armenia and started against Sweden, with Ireland beating Armenia 1-0 at home and Sweden 3-1 away. He was subsequently called into the squad for the October qualifying clashes against Italy and Iceland, although he remained benched for the entire match against the young Italians. Mandroiu is also eligible to play for the Romania national team as his father is originally from Romania.
Career statistics
Professional appearances correct as of 7 March 2020.