The Netherlands international signed a six-year deal with the Magpies on Tuesday night after Newcastle agreed a £6m deal with the Eredivisie champions.
At Ajax I scored quite a lot of goals as an attacking midfielder – sometimes as a striker – and I hope to do that here too
Siem de Jong
De Jong, who memorably handed Manchester City a torrid 180 minutes in the Champions League group stage in 2013, scored 57 goals in 168 top-flight games.
And the 26-year-old, who has six Dutch caps, is looking to be a leader in the Newcastle squad after taking over the Ajax armband from Jan Vertonghen in 2012.
“I hope to bring a lot of attacking play and goals,” De Jong told United’s website.
“At Ajax I scored quite a lot of goals as an attacking midfielder – sometimes as a striker – and I hope to do that here too.
“I want to help the team be as good as it can be.”
“I hope I can bring it here as well,” De Jong continued.
“I had a great couple of years (as captain) at Ajax and really improved my leadership skills.
“It was good for me to be captain and to have that opportunity at Ajax. I hope that will help me here.”
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