That same year, he played his first game for the senior national team and has since earned over 90 caps, representing Serbia at the 2018 and 2022 FIFA World Cup, as well as UEFA Euro 2024.[6] He made his official debut for the club in a Champions League qualifier against Maltese side Valletta, scoring a goal nine minutes after coming on as a substitute.On 1 September, Mitrović provided two assists on his debut for the club after coming on as a substitute at the beginning of the second half in a league match against Zulte Waregem.[14] On 10 December 2013, in the last round of the Champions League Group C against Olympiacos, Mitrović replaced goalkeeper Silvio Proto who had been sent off,[15] but failed to save a penalty from Alejandro Domínguez.[20] On 21 July 2015, Mitrović joined Newcastle United on a five-year contract for a reported £13 million, saying he hoped to be able to play like club legend Alan Shearer.[21][22] He made his debut on 9 August as Newcastle began the season with a 2–2 draw against Southampton at St James' Park, playing the final 15 minutes in place of Papiss Cissé.[28] On the final day of the season, and with Newcastle United already relegated, Mitrović scored the second goal in a 5–1 win over third-place Tottenham Hotspur, but was also sent off for a shin-high challenge on Kyle Walker.[37] On 7 January 2017, Mitrović started the FA Cup third round match against Birmingham City, but was injured in the buildup to the opening goal, scored by Daryl Murphy.Towards the end of December, Mitrović stated in the Serbian sports daily Žurnal that he expected to leave the club in the January transfer window "to find the best solution for my career".[46] On 3 February, Mitrović made his debut for the West London club in a 2–0 win over Nottingham Forest, and almost scored, but his headed effort was cleared off the line by Joe Worrall.[50][51] Mitrović finished the season with 12 goals, four behind top scorer Ryan Sessegnon, as Fulham missed out on automatic promotion on the final day, losing 3–1 to Birmingham City; their first league loss of the calendar year.[57] Mitrović scored three goals in Fulham's next two matches against Burnley and Brighton & Hove Albion, although it was his handball which resulted in a penalty for the latter side, converted by Glenn Murray.[61] While Ranieri was angered by Kamara's decision to take the penalty, Mitrović was more forgiving of the Frenchman, referring to a similar incident he had while playing for Newcastle United.[75] Due to the COVID-19 pandemic, Mitrović did not play for Fulham until the Championship resumed in June, and would be retrospectively banned for three matches for elbowing Ben White in the club's 3–0 loss to Leeds United.[78] On 18 July, Mitrović scored twice and assisted for Bobby Decordova-Reid, in a 5–3 win over Sheffield Wednesday, to keep Fulham's slim hopes of automatic promotion alive.[86] Mitrović spent much of the season in and out of the squad, missing matches due to tactical changes (where he was kept out by Ivan Cavaleiro and Ademola Lookman),[87] various injuries,[88][89] as well as testing positive for COVID-19.[93] His stellar start to the season continued into October as he scored eight goals, including another hat-trick, this time against West Bromwich Albion winning the Player of the Month award for his efforts.[109] On 19 March, in Fulham's FA Cup quarter-final match against Manchester United, Mitrović was sent off after arguing with and pushing the referee, Chris Kavanagh, following a handball decision that saw teammate Willian and manager Marco Silva both sent off.[119] Mitrović was called up by Serbia's U19 coach Ljubinko Drulović for two qualification matches for the 2013 UEFA European Under-19 Championship taking place after his debut with the senior national side against Belgium.[120] Mitrović was also a member of the squad that traveled to Lithuania for the final tournament, where he established himself as one of the key players in Serbia's U19 team which won the competition for the first time in the history of Serbian football.[122] Mitrović earned his first call up to the Serbian senior national team by coach Siniša Mihajlović for a 2014 FIFA World Cup qualifier against Belgium.[125] Two years and a day later, he scored his next international goal, the consolation in a 2–1 friendly defeat to France at the Nouveau Stade de Bordeaux, Serbia's 100th match as an independent nation.[128] He continued this scoring run in 2017, with goals against Georgia,[129] Wales,[130] and Moldova,[131] putting him ahead of teammate Dušan Tadić as the group's top goalscorer.[135] He was also involved in a penalty claim when Swiss defenders Stephan Lichtsteiner and Fabian Schär dragged him to the ground in the box, but referee Felix Brych turned down the appeal.