Arsenal's Hleb to be unveiled by Barcelona today
The Catalan giants will pay the Gunners £12.5m up front for Hleb - with the remaining £2.5m based on appearances and trophies.
But Hleb, 27, agreed a four-year contract with Barca.
The deal is worth around £65,000 a week - almost double his Arsenal salary.
The Gunners signed Hleb from Stuttgart three years ago for £10m.