The 18-year-old won the men’s 100 metres breaststroke SB7 final in a world record-breaking time of 1min 12.50sec, shaving more than a second off his former best mark set just a few hours earlier in the heats.

Victory saw Serrano end Colombia’s long wait for a Paralympic champion, stretching back coincidentally to Pedro Mejia’s triumph in the men’s 100m breaststroke at the 1980 Games in the Dutch city of Arnhem.

While there are other major competitions to focus on before Tokyo 2020, such as the 2017 World Championships in Mexico City and the 2019 Parapan American Games in Peru’s capital Lima, the teenager already has one eye on the next edition of the Paralympic Games in four years’ time.

"I need to continue working and giving the best of myself to maintain my place amongst the world’s best and keep winning titles," Serrano, a five-time Parapan American champion, said.

"My biggest dream is to become the best athlete I can be, to be recognised in Colombia and to compete at every Paralympic Games I can.

"As for Tokyo 2020, I hope I can qualify and lower my times there."

Serrano’s nearest challenger was defending champion Blake Cochrane of Australia, while China’s Hong Yang claimed bronze.

"I feel so proud, so happy, because we had worked very hard with my team in the lead-up to the Paralympic Games," said the Colombian, who last year sealed the world title in the same event in Glasgow.

"I was mentally strong before Rio 2016 and did the best I could in the pool.

"In the end, I even broke my own world record, which was incredible."

Serrano burst onto the international scene at the age of 14 when he claimed multiple gold medals at the 2013 Youth Parapan American Games in Buenos Aires.

At Rio 2016, he also won silver in the men's 100m freestyle S7 and bronze in the men's 50m freestyle S7. 

"I have fulfilled a lifetime dream in Rio," said Serrano.

"Leaving Brazil with three Paralympic medals, taking into account this was my first Games, makes me feel very proud.

"Rio 2016 will be an unforgettable experience for me because it definitively cemented me as one of the world’s best swimmers."

Serrano’s three medals helped Colombia achieve their best-ever Paralympic haul, winning 17 overall - two golds, five silvers and 10 bronzes - which is 15 more than at London 2012.