Piotr Lisek made the most of the absence of world record holder Renaud Lavillenie to take the European indoor polevault title on Friday despite breaking three of his own poles.
Lisek, the only athlete to cross 6m this season, took gold with a clearance of 5.85m, winning on count back from Greece's Konstadinos Filippidis and Polish compatriot Pawel Wojciechowski.
"I didn't have the best preparation in the last few weeks. I snapped at least three poles and I found it hard mentally to cope with this," said 24-year-old Lisek who won the first major title of his career.
"I used old poles and I tried to go as high as possible. This gold medal is of great significance."
Olympic pentathlon champion Nafissatou Thiam of Belgium also shared the limelight on the opening day in Belgrade.
Thiam took gold with personal bests in the 60m hurdles and high jump.
"I have been under scrutiny since the Rio Olympics so I didn't want to come here if I didn't have the capacity to win," she said.
"But the first four events reassured me and I am very happy with gold."
Thiam totalled 4,870 points to finish ahead of Austria's Ivona Dadic (4,767) and Gyorgyi Zsivoczky-Farkas of Hungary (4,723).
In the men's 60m hurdles, Britain's Andy Pozzi, who had the best time of the winter heading into the championships with 7.43sec, took the title.
Pozzi clocked 7.51sec to beat defending champion Pascal Martinot-Lagarde of France (7.52) with Petr Svoboda of the Czech Republic claiming bronze (7.53).
In the women's 60m hurdles, Germany's Cindy Roleder added the title to her outdoor 2016 crown, seeing off Alina Talay of Belarus, the 2015 champion, and compatriot Paula Dutkiewicz.