2025-26: Freshman
In his first fall season, van der Sijs went 2-5 in singles and 1-4 in doubles. One of his singles wins came in his first fall tournament as a Husker at the ITA Central Regional Championships and another came in the Big Ten Individual Championships to conclude his first collegiate fall season. The freshman paired up with Colson Wells and Joan Torres Espinosa in doubles. He was able to record a win with Espinosa at Big Ten Individuals.
Joining the Huskers
Niels van der Sijs, from Eindhoven, Netherlands, signed with the Huskers in November 2024. He will join the roster as a freshman this upcoming Fall 2025.
"We are very excited to have Niels join our family," head coach Peter Kobelt said. "When we go through our recruiting process, we spend a lot of time to identify the right fits for our program. Niels fits these requirements to a T. With the combination of the skills that he has on the court, his work ethic and love for the game, Niels is the full package. There is no doubt in my mind that Niels will come in and emody exactly what it means to be a Husker student athlete."
Before Nebraska
Van der Sijs competed in numerous ITF Juniors Tournaments, highlighted by his win at the 2022 J5 Gazelec. In 2023, the product of Amjoy Tennis Academy reached the semifinals of a three-star Dutch Ranking Tournament. The Class of 2025 senior holds a career-high ITF ranking of 763 and a current UTR rating of 12.15.
Personal
The son of Job and Murielle van der Sijs, Niels has three half-siblings, Rowan, Maxim and Natascha.
Singles
| Year | Spring | Big Ten | Fall | Total |
| 2025-26 | -- | -- | 2-5 | 2-5 |
| Totals | -- | -- | 2-5 | 2-5 |
Doubles
| Year | Spring | Big Ten | Fall | Total |
| 2025-26 | -- | -- | 1-4 | 1-4 |
| Totals | -- | -- | 1-4 | 1-4 |