Romelu Lukaku and Nemanja Matic, the two signings that have transformed United from Europe's most expensively incoherent squad into title contenders, could easily have been wearing blue rather than red now if last summer had played out differently.

Antonio Conte no doubt wishes it had -- particularly in the case of Matic. The Italian pointedly described the midfielder's departure as a "great loss" on the eve of the season, indicating that he had intended to ease £40 million Monaco signing Tiemoue Bakayoko into Premier League life as understudy to the experienced Serb rather than immediately saddling him with the responsibility of being N'Golo Kante's primary partner.

United's hijacking of Chelsea's bid to sign Lukaku was more publicly humiliating but ultimately less consequential for Conte. Alvaro Morata has proven as neat a fit at Stamford Bridge as Lukaku has at Old Trafford, in spite of the fact that, after an excellent start, both men go into Sunday's match without a goal in their last six appearances.

In the corridors of power at Stamford Bridge, however, there are no regrets about either episode, and this internal conviction is unlikely to be shaken even if Matic and Lukaku play key roles in a damaging United win on Sunday.

Make no mistake: Lukaku was Chelsea's No. 1 striker target heading into the summer, and the player himself had been convinced for the best part of a year that he would get his chance to settle what he called his "unfinished business" at Stamford Bridge.

Everton's significant antipathy towards Chelsea -- fuelled by a public tug of war over John Stones in the summer of 2015 -- complicated negotiations, but the Premier League champions insist the only insurmountable obstacle to a deal was Lukaku's outspoken, uncompromising and spectacularly effective agent Mino Raiola.

Sources have told ESPN FC that while Chelsea were prepared to meet Everton's £75m asking price for Lukaku, they refused to countenance Raiola's demand for a sizeable commission on top of the transfer fee -- an amount in the region of £12m. United, having forged a mutually productive and lucrative relationship with Raiola through prior deals for his clients Zlatan Ibrahimovic, Paul Pogba and Henrikh Mkhitaryan, took the opportunity to pounce.

Lukaku's preference for Chelsea was not strong enough to trump an opportunity to play for Mourinho and join United's illustrious lineage of great strikers, and the deal was swiftly done. However, Raiola's tactics were met with significant anger at Stamford Bridge, and sources have told ESPN FC that it is highly unlikely they will look to do business with him in the foreseeable future.

In the case of Matic it was Chelsea's actions rather than their perceived inaction that prompted criticism. Why did they elect to strengthen a title rival and give Mourinho the "stability player" he had been searching for to balance his United midfield?

The first thing to say is that keeping Matic last summer wasn't a realistic option for Chelsea. The Serb had entered the final two years of his contract and shown no interest in signing an extension. In fact, he had to be talked out of leaving by Conte in the summer of 2016, and not even winning a second Premier League title in the season that followed was enough to dull his desire to depart Stamford Bridge. As soon as he became aware of his former manager Mourinho's interest, United jumped to the top of his list of preferred destinations.

But why sell to United in particular? The answer is Chelsea had already identified Bakayoko as a top target with a view to him inheriting Matic's starting spot sooner or later, and once it became clear a sale was necessary they committed themselves to taking the best offer.

Juventus expressed an interest but were unwilling to either match United's firm bid of £40m or consider introducing wing-back Alex Sandro into broader talks. Chelsea, whose position had been made obvious by Matic's omission from the club's preseason tour of the Far East, were left with a tough choice.

Ultimately finances won out. Chelsea's strategy over the last five years has been to balance signings with sales and focus recruitment on players at the beginning rather than the end of their careers, while heavily restricting contractual commitments to those entering, or already in, their 30s. Matic will be 32 by the time the guaranteed three years of his lucrative United deal end.

Conte clearly could have done with Matic in these opening months, given that Bakayoko and Danny Drinkwater both arrived injured and Kante has been sidelined for much of October with a hamstring problem as Chelsea's defence has disintegrated. It must be particularly galling to see the Serb thriving under Mourinho, who never misses an opportunity to poke at his former club or the man who succeeded him as the darling of Stamford Bridge.

Those above Conte, however, are taking the longer view. Chelsea are confident that Bakayoko will prove a more valuable asset over the next three years than Matic, even if their frustrated head coach is no longer around to enjoy the benefits. The short-term narrative of the sale will also reflect less harshly if Manchester City, rather than United, go on to win the Premier League.

None of this is any consolation to Conte, who must find a way to pick his players up from their humiliation by Roma in time to face an elite team and manager itching to make a title statement. If United succeed and Lukaku and Matic show Chelsea what they could have had, the longer view won't be a popular one.