Manchester United are keeping tabs on Benfica defender Ezequiel Garay with the view to a summer move.

The People says United have stepped up their search for defenders capable of replacing Rio Ferdinand and Nemanja Vidic.

Sources close to United say he has been under close scrutiny this season as manager Sir Alex Ferguson plans for the future.

Ferdinand, 34, hasn't yet committed his future to United as he ponders the prospect of a one-year deal at the end of the season.

And with concerns over the durability of skipper Vidic, Ferguson has asked his scouts to identify Europe's top central defenders.

Argentinian Garay, 26, a former Real Madrid star, has impressed and has been watched several times by United spies.