We look at the dealings in three major rivalries and how they might affect the state of play in the Premier League, LaLiga and Bundesliga.
In Europe's three heavyweight leagues, six teams have combined to take maximum points so far this season and appear set to tussle over their respective domestic titles over the coming nine months.
But how has a close-season of wheeling and dealing in the transfer market prepared Manchester City and Manchester United; Barcelona and Real Madrid; and Bayern Munich and Borussia Dortmund for the battles ahead and how do they look after the transfer window closed this week?
Premier League – Manchester City and Manchester United
Attempting to recover from pitiful league campaigns last season, both Manchester clubs lavished funds on their newly incumbent superstar managers. City and United led the way as the latest round of television rights riches allowed England's top flight to break through the £1billion barrier for the first time in a single transfer window, according to figures released by Deloitte.
Nevertheless, Jose Mourinho and Pep Guardiola adopted contrasting approaches. Mourinho might have Henrikh Mkhitaryan still waiting in the wings at Old Trafford in terms of first-team starts, but in Eric Bailly, world-record purchase Paul Pogba and Zlatan Ibrahimovic, he has a made-to-measure spine that has instantly lifted the level from the Louis van Gaal era and propelled United to three wins from three Premier League matches.
Of the nine signings made by Guardiola, only two – John Stones and Nolito – have made their City debuts. This figure is skewed slightly by injuries to Ilkay Gundogan and Leroy Sane, although four of the remaining five are currently playing for other clubs.
Guardiola's main impact has come in reimagining City's playing style in five wins spanning Premier League and Champions League, revitalising an already talented squad. Moving out Joe Hart, Eliaquim Mangala, Jason Denayer, Samir Nasri and Wilfried Bony on loan amounted to a highly successful deadline day for the former Barcelona boss, who prefers to work with smaller group to allow his tactical theories to take hold.
Stones has played with impressive assurance at the heart of defence and Spain forward Nolito has three goals to his name already, but they have been cogs in a well-oiled machine, whereas the impact at United from Bailly, Pogba and Ibrahimovic has been more explosive.
Goalkeeper Claudio Bravo, Gundogan and Sane could all make their debut next time out, when City travel to face United at Old Trafford as Mourinho, Guardiola and their differing methods of tactics and team-building are placed in direct confrontation once more.
La Liga – Barcelona and Real Madrid
It was in this arena that the two Manchester managers first came into conflict and there has been a role reversal of sorts between Spain's two superpowers during the current transfer window.
Barcelona have spent and stocked their squad fairly liberally, splashing out on an shining light at a recent major tournament in the form of Andre Gomes and picking out some prime Spanish talent in Paco Alcacer.
Real Madrid, on the other hand, have been uncharacteristically quiet – almost mute – on the transfer front. Homegrown products being called back from sojourns elsewhere, namely Alvaro Morata and Marco Asensio, have taken centre stage. This show of faith in Madrid's in-house production line has come with Florentino Perez keeping his infamously loose chequebook under lock and key.
"We have a spectacular squad, impossible to improve," he said after watching the big bucks sloshed around elsewhere. Madrid chalking up a 14th consecutive La Liga win against Celta Vigo over the weekend did his claim no harm.
Naturally, Barcelona sporting director Albert Soler believes his squad is "the most exciting in the world". However, the Clasico rivals – who meet for the first time this term at Camp Nou on December 4 – have both made understandable nods towards continuity over recent months.
None of Barcelona's buys are likely to be regular starters in the immediate future, but they are in place to add much-needed depth to a squad that faltered unexpectedly in the final stretch last season. Bravo and Dani Alves moving on and having their first-team berths taken by Marc-Andre ter Stegen and Sergi Roberto signals a succession process Luis Enrique and the club hope can continue to happen organically with their latest batch of young recruits.
At Madrid, Zinedine Zidane's role is more secure than ever given success on the pitch and evidence Perez's trust in him to helm a squad he rates so highly, or he is vulnerable due to not being trusted with multiple millions of euros, depending on your level of scepticism.
Bundesliga – Bayern Munich and Borussia Dortmund
Bayern Munich have largely mirrored Real Madrid in doing very little, apart from kicking the whole thing off by prizing away Borussia Dortmund's captain at the end of last season and stirring simmering bad blood.
Mats Hummels was followed out of the doors at Signal Iduna Park by Gundogan and Mkhitaryan and the recent history of brilliant Borussia having prime talent torn from their grasp when the team looks ready for greater improvement was being repeated.
However, coach Thomas Tuchel and sporting director Michael Zorc have operated with danced jigs on shifting sands and Dortmund do not appear demonstrably weaker, with a healthy helping of youthful verve thrown in for good measure.
Marc Bartra can match Hummels for class on the ball at centre-back, if not grizzled centre-half play, while Sebastian Rode and returning prodigal son Mario Gotze show the road from Munich to Dortmund runs both ways.
Andre Schurrle has a point to prove and should ensure conversation surrounding attacking support for Pierre-Emerick Aubameyang shifts away from Marco Reus proving his fitness. In addition, Tuchel has two of Europe's most exciting young talents in Emre Mor and Ousmane Dembele chomping at the bit.
New Bayern boss Carlo Ancelotti boasts a leading member of that particular list in Renato Sanches, fresh from dazzling at Benfica and making Portugal's Euro 2016 win a touch more watchable. The Italian is still the most significant arrival and 11 unanswered goals against Carl Zeiss Jena and Werder Bremen in the DFB-Pokal and Bundesliga show the Bavarian winning machine is in fine working order, even if they have neglected the old maxim of building from a position of strength.