Janse, 20, was already tied to Ajax until mid-2029, but the club offered him a new contract. The defender has expressed his gratitude towards Ajax, stating that the club's decision to offer him a new deal shows a lot of trust.
In an interview on Ajax's club channel, Janse said: "I find it very nice that the club expresses this trust." He also acknowledged that the club didn't need to do anything, given that he was already tied to them until mid-2029.
Janse spent last season on loan at FC Groningen, where he gained valuable experience. He is now eager to prove himself at Ajax, saying: "You get loaned out with a reason. You want to improve and come back better, to succeed at Ajax. I've made a certain progress. Now it's up to me to take the next step and play."
Janse has played four games this season, including two Eredivisie matches and two Conference League qualifying matches.