Every few years a side is forced to rebuild, to take stock of what they have and sort the wheat from the chaff. When eras come to an end, replacements must blend seamlessly into a successful side and time is not a luxury afforded to those at the top of their game.
For champions Manchester United and manager Sir Alex Ferguson, another summer of spending has a similar focus to all the rest: building for the future. Now that the era of 'Fergie's Fledglings' is coming to a close - with just Ryan Giggs remaining as an abiding memory of how good they were - a new phrase must be coined for the Scot's latest project, but he has the luxury of building from a position of strength.
Now that Liverpool's domestic title record has been matched and surpassed, Ferguson's attention turns to another team who need 'knocking off their perch': Barcelona. Two heavy defeats in Champions League finals over the last three years has highlighted the gulf between two sides considered the best in Europe, but more than that it has highlighted where the manager needs to strengthen; something he has done to the tune of over £50 million this summer.
In the Premier League era, United have been so successful in no small part because of the depth and passionate commitment of their squad. Players like Wes Brown, John O'Shea and Park Ji-Sung have worked tirelessly for their side while fully in the knowledge that they are not guaranteed a first-team place every week. Ferguson has always installed a team ethic into his squad and, now, must ensure that a similar philosophy is accepted by a new breed of players.
With stalwarts of old, Brown and O'Shea, allowed to leave the club to join Sunderland, Owen Hargreaves' terminal injury woes finally seeing his contract run out and a few other fringe players (namely Bebe) given a chance to shine elsewhere, room has been made.
At first glance, the defence looks weaker than it did last year. When three players leave and one arrives, it is hard to argue that a side is stronger; but when that player is Phil Jones it becomes clear that perhaps it is. The former Blackburn defender's versatility will allow United cover both in the defensive midfield role, and at centre-back. He is also more than capable of filling in at full-back and Ferguson will place a lot of faith in the youngster in the coming season as he looks to justify spending around £20 million on him.
The necessity for Jones to plugs gaps in defence should only raise its head in an injury crisis as the statistics of Rio Ferdinand's and Nemanja Vidic's partnership at the back speak for themselves and the emergence of the similarly versatile Chris Smalling into a genuine backup (moving above the inconsistent Jonny Evans) already stands the club in good stead. Especially when you place them alongside one of the best left-backs in the world: Patrice Evra.
Gary Neville's retirement midway through the 2010-11 season forced Ferguson's hand a little in giving more playing time to Brazilian brothers Fabio and Rafael, but their ability to blend into the side (Fabio following his sibling's path into the first-team) has given the team a freshness that was missing.
Indeed, Neville's spirit will be missed but his heavy legs will not be and the replacement of United's core of ageing stars has formed the basis of Ferguson's spending this summer.
The retirement of goalkeeper Edwin Van der Sar was something that the club had been planning for - that much was evident by the quick, targeted signing of Atletico Madrid's 20-year-old goalkeeper David de Gea for around £18 million. The 6' 4", Spanish Under-21 international is almost a Van der Sar clone in appearance and his playing style is not far from the Dutchman's either, which makes him just about the perfect replacement in Fergie's eyes - even if his debut in the Community Shield suggests there is still work to be done.
Finding someone to step into the boots of the retired Paul Scholes, however, has been harder. His new role as a coach at United may ensure that the side reap the benefits of his class in the next generation of youngsters coming through, but does precious little to cover the creative hole next season, even with the emergence of exciting youngster Tom Cleverley.
Ryan Giggs' move inside may persuade Ferguson that he is not yet in need of splashing £35 million on the likes of Wesley Sneijder just yet, but the fact remains that a player of Sneijder's reputation would be most welcome. Too often against quality opposition, United looked shorn of ideas in the central areas as Anderson, Michael Carrick and Darron Gibson failed to convince, but it is not a problem that they have had on the flanks.
With Antonio Valencia returning from injury, Park always willing to give everything for his side in whichever position he is chosen and Nani having one of his best seasons to date, United were well covered on the flanks even before £16 million was spent on England winger Ashley Young.
Young's ability to play off a frontman, as well as fly down the flanks gives him more versatility as he fights for playing time among the star-studded forward line at Old Trafford and he brings the kind of depth that will certainly prove crucial as the season wears on. Ultimately, his arrival heralds the end of an era for a flying Welsh winger, but Giggs' guile in central areas will be invaluable.
The one place that United have not had to strengthen is up front. With the partnership of last year's sensation Javier Hernandez and England's finest Wayne Rooney dovetailing immediately, the champions have the luxury of calling on players of the class of Dimitar Berbatov (last season's top scorer by the way) and the experienced Michael Owen from the bench. Hernandez will be back in a month after suffering a pre-season concussion, while the return of loan trio Federico Macheda, Mame Biram Diouf and Danny Welbeck also gives the frontline an injection of youth, although at least one of these three will probably seek another short-term move before the transfer window closes.
Unquestionably, United's transfer business this summer has made a bold statement of intent to those seeking to usurp them from their Premier League throne. Ferguson's task of ensuring that his new players gel with his established squad is one that he has conducted with aplomb in the past but this year, above all else, European glory is top of the agenda as yet another era of players test themselves in the Theatre of Dreams.
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