Arsene Wenger hopes Andrei Arshavin can prove to be the "influential force" which kick-starts Arsenal's season.
The most protracted transfer of the January window was finally confirmed on Tuesday afternoon, almost 24 hours after the deadline, with the Premier League happy a deal had been "substantively completed prior to the close of the January transfer window".
"Andrei Arshavin is a player I have admired for a long time," said the Arsenal manager. "He is a versatile player with great experience, who will add real quality to our squad."
The Frenchman added: "Andrei is an exciting impact player with a huge amount of ability and has been an influential force with both Zenit St Petersburg and the Russian national team in recent seasons."
Arshavin will be cup-tied for the Champions League, but has vowed to help the Gunners end their trophy drought after completing his "dream" move to Emirates Stadium in a deal which, it is understood, could eventually be worth a club record £15million.
"Arsenal are one of the leading football clubs in the world, with a group of fantastic young players and a great manager," declared Arshavin, who is likely to be allowed some time to build-up full match fitness after the Russian domestic season finished in November.
"I am looking forward to making the Arsenal supporters happy and helping this great club win trophies.
"I am happy to be an Arsenal player, it was my dream."
Arshavin has always been keen to join the Gunners, and is reported to have been prepared to take a pay cut to push through the deal after flying into London by a privately-hired jet.
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