The reigning Premiers have secured the former Ajax Championship-winning captain on a season-long loan from the Eredivisie powerhouse.

An attacking midfielder and striker, de Jong captained the Dutch giants for two seasons before joining English Premier League side Newcastle United in 2014. The move was marred by injury woes and he rejoined Ajax a year ago, but has struggled for game time.

Sky Blues coach Steve Corica said de Jong would shore up his attacking options, given the departures of Golden Boot winner Bobo and Polish wizard Adrian Mierzejewski .

“Siem is a technically gifted footballer and one I believe can be instrumental in success for us this season,” Corica said.

Corica added: “He scores goals and creates them for others as well and he is a player that will excite Sydney FC members.

“You don’t become captain of Ajax without possessing all the necessary qualities for that job and I believe he can bring those qualities to Sydney FC, and help guide our squad this year.

“This is a new challenge for Siem, I’m confident it is one he can embrace, and I’m sure he’ll slot in seamlessly.”

De Jong was joined at the harbourside unveiling by English striker Adam le Fondre who was signed last week.

At Ajax, the six-cap international  competed in the UEFA Champions League, and made over 180 appearances for the club over two spells, scoring 61 goals in that time.  

He was selected by former Socceroos boss Bert van Marwijk in his provisional squad for the UEFA Euro 2012 tournament and initially included in Ajax’s UEFA Champions League squad for this season.

NEXT: De Jong's Top 10  Ajax goals...

“I’m very excited to be representing Sydney FC this season and I’m looking forward to my time in the A-League,” de Jong said.

“I see a lot of similarities between Sydney FC and Ajax, they’re both leaders in their league with a reputation for silverware and I want to uphold that here.

“I want nothing more than success and I’ll help the squad in any way to achieve our goals of winning all of the trophies we compete for this season.”

De Jong will wear the No. 22 shirt and Le Fondre No. 9. He is Sydney's second marquee after former Johnny Warren medallist Milos Ninkovic. 

Sydney has yet to decide whether they will fill their fifth and final visa spot, with much depending on how the current line-up performs over the coming weeks.

Club Chairman Scott Barlow hailed the arrival of de Jong: “In Siem, we have recruited a truly world class footballer and we are excited to be able to bring him to Sydney FC.

“He is a player of outstanding pedigree and at the age of 29 still has some of his best football ahead of him.

“We have every confidence that Siem will complement our already strong squad and play a major role for us this season as we look to win all three domestic trophies and have our most successful Asian Champions League campaign yet.”