Krmar was born in the Croatian town Vinkovci at the outbreak of the Yugoslavian war, his family fled to Boleč, a suburb of Belgrade. He started playing football in Boleč, later moving to nearby Vinča where he was spotted by scouts and brought to Red Star Belgrade. Although he passed the complete youth ranks of Red Star, he first played professionally in the Serbian League West with Mačva Šabac, where he stayed for one year.
The next season, he joined the Kragujevac-based team Radnički 1923, with whom he earned a promotion to the highest league of Serbian football.[2] In his first year in the Serbian SuperLiga, he received minimal playing time and was loaned to Slavija Sarajevo in the Premier League of Bosnia and Herzegovina where he assisted the club in avoiding relegation.[3][4][5] In the summer of 2012, he joined another Serbian SuperLiga club - FK Smederevo where he spent the full season capping 23 games and scoring 1 goal.[6][7]
Europe
In 2013, Krmar had a short spell at Czech's Bohemians Prague where he appeared in 2 matches.[8] His stint in the Czech Republic was followed by a return to the Serbian second division with BSK Borča where he spent the 2013-14 season.[9] He re-signed with Borča the following season.[10] In 2015, he played the autumn season with Mačva Šabac appearing in 14 games and scoring 1 goal.[9]
Canada
In the summer of 2016, he played in the Canadian Soccer League with London City.[11] Krmar helped London secure a playoff berth by finishing eighth in the league's first division.[12] Their participation in the postseason tournament ended in the opening round after a defeat by the Serbian White Eagles.[12]
After the conclusion of the Canadian season, he returned to Slavija Sarajevo for a second spell where he played 7 games.[13][14] He left Sarajevo after they were relegated from the top tier.[15]
Krmar returned to the Canadian circuit in late 2016 to play with Hamilton City.[16][17] In his second season in the league, he helped Hamilton secure a playoff berth.[18] In the opening round of the postseason, Hamilton defeated Scarborough SC.[19] Hamilton's next opponents were the York Region Shooters where they defeated in a penalty shootout.[20] He appeared in the championship final match where the Serbs defeated Hamilton for the title.[21]
Return to Serbia
Following his second Canadian stint, he returned to the Serbian second tier in the fall of 2016 to sign with Bežanija.[22][23] Krmar was acquired by league rivals Sloboda Užice in the 2017 summer transfer market.[24]
In 2020, he was recruited to join FK Dinamo Pančevo in the Serbian League Vojvodina.[33] He left Dinamo in the 2021 winter transfer market, to join Smederevo 1924.[34] The following season he signed with FK RSK Rabrovo.[35] Krmar would play the remainder of the 2021-22 season with FK Leštane.[36] In the summer of 2022, he played with FK Hajduk Divos.[37] After a season with Hajduk, he signed with FK Boleč Grocka.[38] He was transferred to NK Dunavac Grocka in the January 2024.[38]
^Pasagić, Darko (5 March 2012). "Борац креће у потјеру за Жељезничарем" [The fighter goes after the Railwayman]. Glas Srpske (in Serbian). Retrieved 6 August 2024.
^Pasagić, Darko (12 February 2012). "Бурна зимска трговина" [Stormy winter trade]. Glas Srpske (in Serbian). Retrieved 6 August 2024.
^"Pavlović „kupi" igrače Radničkog" [Pavlović "buys" the players of Radnički]. srpskifudbal.rs (in Serbian). 4 July 2012. Archived from the original on 7 July 2012. Retrieved 6 August 2024.
^"Igor Krmar - Footmercato.net". Foot Mercato : Info Transferts Football - Actu Foot Transfert. Retrieved 23 September 2016.
^Škorić, Edmir (19 January 2016). "Slavija počela s pripremama" [Slavija started preparations]. sportsport.ba (in Croatian). Retrieved 6 August 2024.
^Škorić, Edmir (7 June 2016). "Ispali iz Premijer lige, pa se razbježali" [Relegated from the Premier League, then scattered]. sportsport.ba (in Croatian). Retrieved 6 August 2024.
^Spasojevic, Marko (24 July 2017). "Prvi dolazak u Slobodi" [First arrival in Sloboda]. penal.rs (in Croatian). Archived from the original on 17 August 2017. Retrieved 6 August 2024.