[7] In 1936, while playing football for the local club NK Grafičar, Mihalić met Stjepan Bobek, three years his junior.

[1][7] This was the beginning of a lifelong friendship,[1] as both Mihalić and Bobek (who would become the all-time top scorer for the Yugoslavia national team) were transferred to Belgrade after World War II as Yugoslav star athletes.

[1] He was fairly successful, being able to score top ten finishes competing against the best Croatian cyclists of the era.

[1] However, his enthusiasm for the sport was dampened by a number of major crashes he suffered in training and racing which resulted in injuries and permanent scarring.

[1] Despite the fact that he entered the first foot race in his life without any training, he placed second out of approximately 200 participants, narrowly losing to an experienced athlete.

He won several international competitions, set five national records and was named Croatian Sportsman of the Year three times.

[8] Mihalić got a well-paid job and good conditions for training with his new club, so he decided to settle permanently in Belgrade, where he soon married and became a father.

[1] One of Mihalić's early international successes came at the 1951 Mediterranean Games in Alexandria, where he won the 10,000 m silver medal, behind Alain Mimoun.

[4][11] Mihalić left his mark on the Saint Silvester Road Race in São Paulo, Brazil, where he won twice (1952 and 1954), once placed third (1951) and once second (1953, losing to Emil Zátopek).

[4][14] Mihalić himself judged that, in a field of 46 Olympic marathon entrants, 15 were better than him,[1] but nevertheless he felt that he had a fighting chance for winning a medal.

[4][20][21] Mihalić's winning time of 2:25:54 was five minutes short of Kelley's course record established in the previous year, but was still impressive given the hot weather in which the race was held.

[21][22] The "heat-loving Yugoslav's"[23] successes in hot conditions were attributed to his unusual habit of training in the middle of the day, between noon and 2 pm.

[1] He then promptly switched to racewalking and won three gold medals in the 5 km event for Serbia and Montenegro at the veteran Balkan Games, the last one in 2005.

[1] In his late 80s Mihalić still walked 3 kilometers every day from his Belgrade home to the Partizan Stadium, where he volunteered as an athletics coach.