Sir Alex Ferguson is deciding on whether to give his squad a shake-up. Sunday could see United become the first side to lift four successive Premier League titles, but whether or not they beat Chelsea to the crown, a mini-sale could still be on the horizon this summer. "I will have to decide how I can improve the team," said Ferguson. "Is it time to build a new team because when you are challenging for four leagues in a row, the Champions League, the FA Cup and League Cup and the Club World Cup there is a draining effect. "You have to be aware of that and spot the moment when you say it is time to freshen and change one or two players. "It is not a desire to do it, it is a need to do it because the demands and pressure on players to do it can be quite exacting." With old guard Edwin Van der Sar, Gary Neville, Ryan Giggs and Paul Scholes on new one-year Old Trafford deals they are exempt from the dismantling job. The likes of Wayne Rooney, Patrice Evra, Darren Fletcher and Jonny Evans, who will receive a new five-year contract imminently, plus the bulk of the younger end of the senior pool are also likely to escape. But the spotlight could fall on Michael Carrick, Dimitar Berbatov, Ji-sung Park, Tomasz Kuszczak and Ben Foster. Ferguson's rebuild has already begun and he has hailed the solid base his youngsters can provide. "People don't recognise we have signed three players for £20m in Chris Smalling from Fulham, Mame Biram Diouf from Molde - he has done well - and Juan Hernandez from Mexico will join after the World Cup. "They are young players whose futures are guaranteed at the club. Other young players come into that bracket like Kiko Macheda, Gabriel Obertan and Danny Welbeck. Darron Gibson is starting to emerge very strongly. "Jonny Evans has proved himself at 21 and has signed a new contract. We have a good foundation of young players who can carry the club for a long time now." The United boss also hailed the club's Player of the Year contenders. The fans award and player's player honour went to Wayne Rooney, but Fergie pinpointed the contributions of others. "If you look at the defensive side of things this season everyone is aware that our defence has been decimated throughout the season at different times," he stressed. "Only Patrice Evra has played all the way through. We gave him a rest at Blackburn but other than that he has played every league match and that is an astonishing achievement. "Thankfully we had him in all these games. He came into the category of an outstanding season. Darren Fletcher's emergence in the team is another one. "Paul Scholes was phenomenal in the second half of the season and then you have Valencia doing so well on the right hand side and then you turn to Wayne Rooney. "His form this season has been absolutely electrifying. It has lifted everyone. "He has practised more this season. He has concentrated on that part of how we see him as a centre forward. "Being as high up the park as he can be, being a threat behind and being in the box all the time. That has worked. It has paid dividends." But the Reds' grip on the Premier League trophy is now weak with Chelsea strong favourites to beat Wigan on the final day at Stamford Bridge and snatch the trophy on Sunday while United entertain Stoke. Fergie, however, won't be beating himself up about points dropped in the past nine months. "You can torture yourself with that. For instance losing at Burnley you can say to yourself crikey we have just started the season and have lost three points," he added. "We missed a penalty that night and if we had got that we probably would have won the match or got a draw at least and that would have made the difference, who knows? "You look at the bad decision at Chelsea and then the one against them at Old Trafford. You can look at all these twists and torture yourself but there is no point. It happens. We sometimes get breaks ourselves so you have to take the bad with the good." UNITED have taken French-born keeper Rais M'Bohli on a two-day trial from Slavia Sofia in Bulgaria. The 6ft 3in 24-year-old from Paris is in Algeria's provisional World Cup squad.