This might seem like a biased choice, and maybe it is a little, but I definitely stand by it.
Andrey Arshavin brilliantly led Zenit to the UEFA Cup title and Russia to the semis of Euro 2008 with absolutely brilliant performances.
He contributed to Zenit's European success with an amazing four goals and 10 assists! In Euro 2008, he was Man of the Match in every match he played except in the semis against Spain.
Arshavin was so impressive that many top clubs around the world tried to sign him, but Zenit initially refused to sell him. He was eventually signed by Arsenal in January 2009 for 15 million euros.
He's had his brilliant moments at Arsenal (especially his awe-inspiring four goals at Anfield), but Arsene Wenger has failed and keeps failing to take advantage of the Russian's huge talents by playing him completely out of position. Despite Wenger's blindness, Arshavin still manages to have pretty good stats. This season, he has already scored five goals and had five assists.
Fortunately for opponents, he hasn't managed to produce his best (or even near it), and he will never do it under Wenger.
He is still 29, and he will hopefully move to a top European club in time so that he can compete for trophies like he deserves.
He has said in an interview that he dreams of playing for Barcelona, and I'm sure that any Barcelona fan who has witnessed the Russian play at his highest level would definitely welcome Arshavin.