South Korean rhythmic gymnast Son Yeon-jae captured four medals at an International Federation of Gymnastics competition in Bulgaria on Sunday (local time), including a gold in clubs.

At the season's sixth FIG World Cup in Sofia, Bulgaria, Son scored 18.550 points in clubs to finish atop the podium. Ganna Rizatdinova of Ukraine won the silver at 18.450 and Arina Averina of Russia took the bronze at 18.300. Yana Kudryavtseva, a three-time world all-around champion, was fourth at 18.250 after she dropped her clubs during the performance.

This was Son's first World Cup gold medal since winning a ball event at the season's first World Cup in Espoo, Finland, in February.

In other apparatus finals on Sunday, Son won silvers in both hoop and ribbon, and claimed a bronze medal in ball.

Son earned 18.650 points in hoop, which was her personal best in the World Cup competitions. She surpassed her previous record by 0.100, but it wasn't enough to claim the gold after Rizatdinova scored 18.800. Averina was third at 18.550.

In ribbon, Son was second after finishing 0.450 points behind Kudryavtseva who had 18.900. Rizatdinova took the bronze at 18.100.

In ball, Son was third with a score of 18.550. Kudryavtseva was the winner at 19.200, followed by Rizatdinova at 18.800.

Son wrapped up the Sofia World Cup with five medals. On Saturday, Son claimed the bronze in the individual all-around with a career-high score of 74.200 points.

The Sofia World Cup is Son's fourth World Cup this season and her first since the Pesaro World Cup in Italy that was on April 1-3. She skipped the World Cups held in Ukraine and Belarus earlier this month to save her energy and not overexert herself.

Son's performance in Bulgaria also means that the 22-year-old has now collected medals at every World Cup this season.

At the Espoo World Cup in February, she took a gold medal in ball, silvers in individual all-around and ribbon, and a bronze in hoop. At the Lisbon World Cup in March, Son finished runner-up in ball and clubs, while finishing third in hoop. At the Pesaro World Cup in April, she won silvers in ribbon and clubs.

Son is trying to become the first South Korean rhythmic gymnast to win an Olympic medal in Rio de Janeiro in August. She ranked fifth in the individual all-around at the 2012 London Olympics. (Yonhap)