After losing both Tevez and Ronaldo this summer, Sir Alex must now focus on building his fourth (and last) great squad.Certain Manchester United fans, who are still able to count their age without taking their shoes and socks off, may be a dash worried about how the summer has started. Popular surnames on the backs of replica jerseys will soon need replacing, and no longer will goals from two of Uniteds most impre sive players over the last two seasons be recreated in gardens and parks every Sunday morning. Elder patrons will be able to console the younguns with wisened stories of years past; about players who had shone in the theatre of dreams, yet departed in their prime; squads so memorable that you can still remember the starting 11 of that final. Fans of any other team would be bemoaning the sale of two irreplaceable squad players as the end of an era, but interestingly, even though George Hill Jersey that may be the case for United, there may be one last trick up their managers sleeve.Every team has had at least one great side, some are lucky to have had a couple, even if theres a forty year gap between them. Most great teams are linked to a great manager: Paisleys great Liverpool side, Revies Leeds, Cloughs Forest. Yet what is unique about being a United fan is that for the last twenty four years, the Ferguson years, they havent had just one great side, theyve had three. Could now be the time to build the fourth?Sir Alexs first great squad actually began life soon after he had completed his first season after taking over from Ron Akinson in November 1986, with the purchase of Brian McClair from Celtic. It wasnt all plane sailing from day one; as the much repeated story goes, Fergie was close to the sack in September 1989, had it not been for a hard-fought FA Cup win, this after bringing in future legends such as Ince, Pallister and the returning Hughes.It wasnt for another two years that the first great side started to take shape. Nine of the starting eleven that beat Barcelona in the 1991 Cup Winners Cup final had been purchased by Ferguson who was, prior to this, still a manager having trouble bringing in the exact players he wanted to; Beardsley, Hateley and Gasgoigne were all turning down Ferguson long before Hirst and Shearer a few years later. Post Josh Hart Jersey -European succe s brought this to change; Schmeichel was the solution to a long term goalkeeping problem, Kanchelskis was the first out-and-out winger since Coppell, and then there was a little known zippy youngster with Darius Miller Jersey a huge potential; Giggs. With the core of the side starting to gel, and the new signings, including a certain Eric Cantona, the side won the league in 1993, however Fergusons first great side wasnt achieved until a year later, after one more important signing in Roy Keane. The 1994 Cup Final win against Chelsea was a great end to a fantastic season; 16 million-worth of signings in a starting 11 that took 8 years to build.However within twelve months, Hughes, Ince and Kanchelskis all left for different clubs a combined 14million, which left a lot of critics questioning Ferguson again, especially after the replacements were a handful of youth team graduates that anyone outside of Old Trafford had seen little of. Yet what Ferguson had at his disposal were the beginnings of his second great side.The survivors from the Chelsea Cup Final; Schmeichel, Irwin, Giggs and Keane, were partly joined by young talented, homegrown English internationals like Gary and Phil Neville, Nicky Butt, Paul Scholes and David Beckham, and experienced foreigners such as Ronny Johnsen, Jaap Stam, and Dwight Yorke. Four years in the making, Fergusons next squad peaked in 1999; the treble year. A midfield without Scholes and Keane saw Bayern Munich control much of the Champions League final, until the last Tony Carr Jersey few minutes at least. When considering the best eleven from this era, mixing the Champions League Final starting eleven with the FA Cup Final eleven from just four days prior not only shows the quality of players, but the depth in the squad.Fergies latest great side took longer to build than he would have liked. Soon after the treble, Schmeichel left for Portugal, leaving a huge void in the goalkeeping position (much like the one he solved 9 years earlier) that took 6 years, and countle s replacements to fill. Stam left to Italy a few years later, despite Ferguson later admitting it was a mistake. Bigger names such as Beckham, van Nistelrooy, and Keane all left Old Trafford in their prime, much like Ince, Hughes and Kanchelskis (and to a latter extent, Cantona) had done in the 90s. Cup finals or league wins were neither impre sive, or memorable; the 3-0 victory over Millwall in the 2004 Cup Final had the beginnings of a good side, but was still weak in too many areas, a fact that was made apparent a year later in the defeat by Arsenal. It had started to look better by the 2006 League Cup Final win against Wigan. Signings such as Evra, Carrick and Vidic in that year had worked, and with the form of players such as Ronaldo, Rooney, Vidic and Ferdinand, the side were looking stronger than ever. By the time of summer 2008, the side had peaked, a win by penalties against Chelsea in the Champions League had capped a fantastic season.However, over the last 12 months, and with the summer transfers so far, it appears Ferguson has entered yet another rebuilding stage. Stars such as Giggs, Neville, Scholes and Van der Sar will not be first Derrick Favors Jersey team regulars for much longer, and with the lo s of two highly regarded players in Tevez and Ronaldo, it appears that United need to refresh, and rebuild once again. Some positions could already be considered taken, the Brazilian twins Rafael and Fabio have looked promising in their debut season, Rooney is still just 23, whilst youngsters like Darron Gibson, Anderson and Macheda have enough potential to succeed.With Ferguson no closer to retiring, United have the best man with which to achieve even more succe s.