“I’m really happy. We had a good season and I want to build on that,” he told the club’s website (www.ajax.nl)
“The results we have achieved so far were fantastic and it will be a hell of a job to repeat them. But we will set ourselves goals and seek to achieve them,” the 49-year-old added.
Ten Hag's original contract was due to end in mid 2020.
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“We are looking forward to the next years with a lot of confidence,” added club director Marc Overmars.
“We think it’s important that after such a successful season the coach stays to work on building on the success.
“That will not be easy, of course, as certain players will leave, but we hope to temper that well. Erik has to create another team to watch out for and we have the confidence he will do so,” he said.
The Dutchman's young team won a lot of plaudits during their unexpected run to the Champions League semi-finals. En route, they knocked out holders Real Madrid and Serie A champions Juventus.
Ten Hag took charge of Ajax in December 2017 after the club fired Marcel Keizer.
Ten Hag worked alongside Pep Guardiola at Bayern Munich, where he coached the club’s reserve team, before returning to the Netherlands to take charge at Utrecht in 2015.
During his first two seasons with Utrecht, he guided them to fifth and fourth-place finishes.
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