The England defender, 32, rose through the ranks at the Hammers famous Academy and into the first team as a teenager under Harry Redknapp in 1996.
On a prayer: Ferdinand hopes the Hammers bounce back up after their demotion to the Championship
Ferdinand spent seven years in total at Upton Park before completing a then record ?18million move to Leeds - another club he hopes will return to the top flight in 2012.
'West Ham was the team I grew up in as a kid and to see them relegated out of the Premier League was disappointing,' he told MUTV.
'It was always nice to go back and play against them and see old faces and old friends but this is football and things change, things happen.
'My other old team Leeds are in the Championship now as well so times change. I just hope they come back up again next season.'
Hammer time: Ferdiand came through the West Ham Academy before he was sold to Leeds
Earlier this summer Ferdinand's younger cousin Kane was linked with a move to Sam Allardyce's side from Southend, while his brother Anton was part of the club's 2006 FA Cup final team.
But whether there is a Ferdinand family claret and blue influence in east London or not, Rio insists he will always hold the Hammers dear to his heart.
'I'll always look out for West Ham's results,' he added. 'When I was young they gave me my chance to become a professional footballer and I'll always keep the club close to me.
'More importantly now, I'm a Manchester United player so this is my club. I look out first for us and the secondly for the other teams.'
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