The Gunners midfielder is almost certain to leave the Emirates this summer after admitting he has failed to adapt to life in the English capital.
The 27-year old has spent three seasons with the Premier League giants playing over 100 times in the process.
"There are a couple of positions that we can improve and that needs to be strengthened to have the necessary balance," Real boss Bernd Schuster told AS.
"Over the past two months we have had a plan and we know what we want, but now Hleb has been added.
"We did not know he could leave Arsenal but in recent days it has been more positive. We were surprised that he might leave there."
I personally think Hleb would be a terrific player in La Liga although I feel it is a real shame that he is leaving the Premier League.