He was the Polish League (Ekstraklasa) Player Of The Year in 2010 beating current Bayern Munich star Robert Lewandowski to the top award, while his combined career transfer fees total over $12 million.
His transfer to Trabzonspor in 2011 reportedly produced a record fee ($7.82m) for a Polish League player which stood until English Premier League club Southampton purchased Jan Bednarek last month.
A season later he was a member of the Poland national team which took part in the Euro 2012 Championships in his home country.
The 40-capped midfielder brings extensive experience to the Sky Blues, having played in the UEFA Champions League and UEFA Europa League for Turkish side Trabzonspor, as well as in the AFC Champions League for Saudi Arabian club Al-Nassr.
Mierzejewski put pen to paper today on the deal after completing a medical with the Sky Blues.
Head Coach Graham Arnold said: “Adrian’s signing is a major coup for the club as he brings with him a huge amount of playing experience, quality and excitement for our Members.
“He is a player I believe will add more of the x-factor to our front line.
“After speaking to Adrian, he ticked all the boxes with his character and I look forward to working with him.”
The 30-year old says he is excited about his new challenge and the chance to make a name for himself in the Hyundai A-League.
“I’m extremely pleased to be joining the Hyundai A-League double winners and can’t wait to begin the challenge of improving on last season.
“Sydney FC are a famous club and one I am very proud to be joining.
“There is a big challenge ahead of us with the added excitement of an AFC Champions League campaign.
“I have spoken with the Head Coach and I know we have a very big and exciting season ahead.”
Adrian's Player Partner is Esko Property Services. Click here for their homepage.
Click here to watch some of the Polish international’s skills.
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