Sarel De Jong has had an extensive amateur career prior to becoming a professional fighter. In 2016 she entered the WAKO Senior European Championship at 65 kg, where she placed third. In 2017 she first entered the Hungarian Kickboxing World Cup at 65 kg and earned a second place finish. Two months later, at the World Games, she won the gold medal at 65 kg. She participated in the November WAKO Senior World Championship, where she won the silver medal at 65 kg In 2018 she entered only one competition, the WAKO Senior European Championship, where she won the gold medal at 65 kg. In 2019 De Jong entered four tournaments. She won the gold medal at 65 kg during the Yokoso Dutch Open, as well as further gold medals at the Austrian Classics and Hungarian Kickboxing World Cup 60 kg tournaments. De Jong ended her amateur career with a third place finish at the WAKO Senior World Championship.
Professional career
De Jong made her Enfusion debut during Enfusion Rookies, when she fought Krystina Lexova, and won the bout by unanimous decision. During Enfusion: Kickboxing Talents 33, she fought Sadie Siem, winning the fight by unanimous decision. At Enfusion Live 69, she faced Chellina Chirino for the Enfusion 64 kg title. De Jong won a unanimous decision. In her next fight with the organization, she fought Samira Kovacevic for the 61 kg Championship. De Jong won the fight through a fifth round TKO and became a champion in two weight classes. During Enfusion 76/77 De Jong fought Victoria Lomax. She won the fight in the third round, by knockout. Sarel De Jong suffered her first loss with the organization during Enfusion 78, when she faced the veteran Anke Van Gestel. The loss came by way of a split decision. She next faced defended her 64 kg title against Sanne de Ruiter. De Jong won by unanimous decision. Sarel De Jong would then defend her 61 kg title, fighting at Enfusion Groningen against Madelen Søfteland. Sarel won the fight by unanimous decision. De Jong faced the WAKO champion Mallaury Kalachnikoff in a non-title bout at Enfusion 91. De Jong won a unanimous decision. At the end of 2019, Enfusion voted her the Best Female Fighter of the Year. Sarel de Jong was scheduled to fight Michaela Michl for her second 64 kg title defense. The fight was cancelled due to the COVID-19 pandemic. De Jong is scheduled to defend her 61 kg title against Aylina “The Angel” Engel on September 19 and her 64 kg title against Michaela Michl on November 21.