Sir Alex Ferguson has confirmed that Northern Ireland defender Jonny Evans has signed a new four-year contract with Manchester United.After spending a couple of spells on loan at Sunderland, Evans has made huge progress in the last two seasons. [LNB]Evans has made 64 first-team appearances for United and has shown himself good enough to stand in for injury-prone Rio Ferdinand. [LNB]"Jonny has proved himself," Ferguson told MUTV. [LNB]"We have been working on it for a few months now and I am happy that he has signed it", said Ferguson of the new contract. [LNB]"Jonny Evans has played a lot of football this year. For a centre-half at 22 years of age to play so many games and show the quality he has, is tremendous."[LNB] Fantastic news. Whenever he's playing he always impresses me and I'm glad he's staying at our great club redevilmatth The Belfast-born player, who has won 20 international caps, is being tipped as a future club captain at Old Trafford. [LNB]Ferguson let slip at Tuesday's player-of-the-year awards that Evans had agreed a new deal, which was confirmed on Friday. [LNB]Meanwhile, Ben Foster has been given no guarantees over his status at Old Trafford. [LNB]The goalkeeper admits he is considering his future after playing only one first team game in the past seven months, dashing his hopes of making England's squad for the World Cup. [LNB]"I have had a chat with Ben. I understand his dilemma but there is nothing I can do", said Ferguson. [LNB]"He is a terrific goalkeeper and we will see what the future brings for the boy. He has the talent to be England's goalkeeper and we're conscious of that. [LNB]"We'd like to help but unfortunately he's not played enough football to get him on that plane to South Africa." [LNB]Foster admits that his future could lie elsewhere, especially after 39-year-old first-choice Edwin van der Sar decided to extend his career by a further season. [LNB]"You never want to leave Manchester United," Foster, 27, told the Manchester Evening News. "If you leave this club you are only ever going to go down but I want to be playing football. [LNB]"I am not interested in just hanging around and I would go if the club wanted to sell me. [LNB]"If they are happy to accept a bid then you have to read between the lines and realise you are not really needed and move on. It would not be the end of the world for me."