Sir Alex Ferguson may add just one more player to his Manchester United squad this summer as he plots to regain the Premier League title from Chelsea. United chief executive David Gill has indicated funds are available to his manager to spend this summer, but Ferguson revealed he is happy with the balance of his squad. The United manager has already signed rising Mexican star Javier Hernandez from Guadalajara and defender Chris Smalling from Fulham, and a raft of new faces had been expected to follow with French duo Franck Ribery of Bayern Munich and Real Madrid's Karim Benzema among those linked with the Reds. But Ferguson revealed last night he will place his trust in United's existing squad and his latest crop of youth and reserve players if he is unable to pinpoint any new signings. Speaking alongside Gill at a press conference in New York to promote United's four-game North American tour this summer, Ferguson said: "In the market today it's very, difficult and the structure of our squad is good in terms of ages, balance, numbers and there's a lot of good young players. Future "Sometimes you have to trust in all the development of the last few years and I'm going to stick with that, or most of it. "There may be one signing and maybe we'd like to get a good player to the club, of course, but it's not easy in the present day climate and I've nothing definite to tell you because we're still assessing whoever's available and the difficulties in terms of who you'd bring in." Gill added: "The other point to bear in mind is the Premier League is bringing in squad limits next year of 25. "There will be unlimited under-21s and other rules and we'll be taking all that into consideration." To that end, Fergie said he would not be replacing goalkeeper Ben Foster, instead he'll promote England Under-21 international Ben Amos to the first-team squad. Foster is close to completing a £6m move to Birmingham and the United manager is confident 20-year-old Amos has a bright future at Old Trafford. "When we decided to let Ben (Foster) go, we were in the process of letting a good young goalkeeper, Ben Amos, go out on loan," Ferguson said. "He's in the England Under-21 team, he's very talented and has a good future ahead of him."