Foster is the latest guest on the UTD Podcast and provided an honest assessment of his time with the Reds, including making the step up to Old Trafford, after impressing Sir Alex Ferguson during a loan spell at Wrexham.
A first England call-up for Foster came in 2006 from ex-United assistant manager Steve McClaren, during the keeper's first loan spell with Watford - where now plays on a permanent basis.
"At the end of the second year at Watford, I got called into the England team as a standby goalkeeper so I saw the standard of what England was like," Foster revealed.