Tomašević was one of the best forwards in the Belgrade clubs in the period before the World War II, the star player of BASK, national team striker and an excellent manager.
His debut was in Belgrade on 15 March 1931 against Greece (4-1 win) having scored a hat-trick.
There was a darker period in his national team career that happened after in a match for the Balkan Cup, in Sofia against Bulgaria (2–3 loss), he failed to materialize a penalty and was afterward absent from the national side for three years!
His comeback was in a Balkan Cup realized in Athens in 1935 and was a perfect opportunity for him to demonstrate the unfairness of his absence, having shown great condition and scored three goals in two matches that much helped his side to win the tournament, whereas Tomašević himself was the best scorer (along with Tirnanić with 3 goals each).
He was the main coach of Sarajevo's FK Željezničar, Ljubljana's clubs Krim and Odred, Vardar Skopje[2] and Partizan Belgrade but his main achievements were the two national cups with Red Star Belgrade, one national championship with Hajduk Split and winning the promotion to the First League with Radnički Beograd.