Born in Teslić, SR Bosnia and Herzegovina, Yugoslavia, he began his career in 1963, with local club FK Proleter Teslić. He was picked up by bigger club FK Borac Banja Luka the next season. He turned down an offer from Croatian Giants HNK Hajduk Split and went on to play with many Yugoslav clubs including three first division clubs NK Olimpija Ljubljana, FK Radnički Kragujevac, and Yugoslav power house FK Partizan although only playing two matches, both friendly. He finished his European career playing with FK Spartak Subotica and FK Pelister in the Yugoslav Second LeagueStats from Yugoslav First and Second Leagues at B92 (copy of zerodic.com) before coming and playing professional in the United States for Fort Lauderdale Strikers in 1978. After a season he went on to play for ASL's Columbus MagicBrett, Dave. "Scores a Hatrick (3goals) to Get Columbus Magic the Win" NCR September 13, 1981. He also played in the National Soccer League in the summer of 1976 with the Serbian White Eagles and Windsor Stars. In 1981, Mršić signed with the Cleveland Force of the Major Indoor Soccer League. He then moved to Canada where he finished his career with Toronto Croatia.Franjic, Stipe. "Toronto Croatia sign Ivan Mrsic", Toronto Sport June 27, 1983.Sovic, Miodrag ."Kk Ljubljana Igra Protiv Sibenik do a I Pobidju 3–1 List a Strelac Mrsic." Ljubljana Vrjeme. October 17, 1970.Petkovic, Simo. "Lleaving His Home Town Club Proleter Tesilic!" Jugoslovenski Sportski List. May 17, 1966.Petkovic, Simo."Five New Players Including Ivan Mrsic Sign Pro Contracts for Fk Pelister Bitola." Jugoslovenski Sportski Jurnal, 1976.Petrovic, Goran "Vracam se Proletaru Ivica Mrsic Grad a Teslicu" February 14, 1969. Grad Teslic Danas VjernjiSuljakovic,Safet. "Jedinstvo Igra I Mrsic Jedinstvo Bihac Pobjedu." SportskI Grad Bihac. July 19, 1973.Suljakovic,Safet. "Ivan Mrsic Scores in Season Debut for, NK Jedinstvo Bihac." September 14, 1972. Jugoslovenski Sportski Jurnal.Markovic,Sinisa." Novi Graca za Fk Radnicki Kraguejevac Ivan mrsic". Jugoslevenski Sportski Journal. July 1971.
