Guilherme Costa

He competed in the men's 1500 metre freestyle event at the 2017 World Aquatics Championships, finishing in 19th place.[2][3]

On 6 December 2017, participating in the Brazil Open (long course) in Rio de Janeiro, he broke the South American record in the 1500-metre freestyle, with a time of 14:59.01.[4] It was the fourth time in 2017 that he broke the South American record of this race.[5]

At the 2018 South American Games in Cochabamba, he won the gold medal in the 400m and the silver medal at the 1500m freestyle.

On 30 June 2018, participating in the Sette Colli Trophy (long course) in Rome, he broke the South American record in the 800-metre freestyle, with a time of 7:50.92.[6]

At the 2018 Pan Pacific Swimming Championships in Tokyo, Japan, he finished 4th in the Men's 4 × 200 metre freestyle relay[7], 4th in the Men's 800 metre freestyle[8] and 4th in the Men's 1500 metre freestyle.[9]

At the 2019 World Aquatics Championships in Gwangju, South Korea, he finished 21st in the Men's 800 metre freestyle,[10] and 25th in the Men's 1500 metre freestyle.[11]

At the 2019 Pan American Games held in Lima, Peru, Costa won his biggest title, the gold medal in the Men's 1500 metre freestyle, with a time of 15:09.93.[12] Brazil has not won this event at the Pan American Games since Tetsuo Okamoto won it in the first edition of the Games, in 1951.[13]

In December 2019, participating in the U.S. Open (long course) in Atlanta, he broke the South American record in the 400-metre freestyle, with a time of 3:46.57,[14], in the 800-metre freestyle, with a time of 7:47.37 [15] and in the 1500-metre freestyle, with a time of 14:55.49. [16]