[2][4] He then collected two of the most prestigious trophies of the year at Petits As and the European Junior Championships at Plzeň,[4] beating Borna Ćorić and Kyle Edmund, respectively, in the finals.

[2][4] In 2012, Milojević won five ITF titles across all four surfaces, winning in Malaysia and Manila on hardcourts, in Halle (Westfalen) on grass, Nagoya on carpet, and in Mexico City on clay.

He was also invited for a semifinal clash against France in 2017, but instead chose to play in a Challenger tournament in order to improve his ATP ranking.

Milojević partnered with Danilo Petrović for the 2018 Davis Cup World Group play-offs vs. India in September.

In September 2020, Milojević reached the second round on his debut as a qualifier in a Grand Slam main draw at the 2020 French Open, where he won his first match against fellow Serbian Filip Krajinović in four sets 6–4, 3–6, 6–3, 6–1.

[13] After winning his third Challenger title at the 2021 Zadar Open in Croatia by defeating Bulgarian Dimitar Kuzmanov, Milojević reached his best career-high ranking of No.

After the Australian tour, he reached the quarterfinals as a lucky loser at the Córdoba Open where he lost to Juan Ignacio Londero.