The top two sides in the country will put forth a plethora of talent at one of its most famous arenas this weekend, but which players win the nod to get into this combined Manchester XI?
Unfortunately for the likes of the suspended Paul Pogba and injured stars including Benjamin Mendy and John Stones, only players available to feature this weekend are eligible for our team.
So, Reds, Blues and neutrals, read on – you'll almost certainly disagree strongly…
David de Gea (Manchester United)
Ederson might well be the most influential signing Pep Guardiola made during the previous transfer window, breathing confidence into a previously fragile City backline, but De Gea has a legitimate claim to being the best goalkeeper on the planet – one only strengthened by his ludicrously brilliant display in last weekend's win at Arsenal.
Antonio Valencia (Manchester United)
It is easy to forget Valencia was signed as a winger from Wigan Athletic in 2009 and initially charged with the impossible task of filling the void left by Cristiano Ronaldo at Old Trafford. The Ecuador international has since reinvented himself as one of the most dependable full-backs in the business and edges out Kyle Walker, despite the strides the former Tottenham man looks set to make under Guardiola.
Chris Smalling (Manchester United)
Out of favour with England, United fans will not want to dwell upon where they might be without Smalling. The towering centre-back has made light of injuries to colleagues Phil Jones and Eric Bailly – not to mention Victor Lindelof's unsure start to life in England – to help Mourinho's backline become the most miserly in the top flight.
Nicolas Otamendi (Manchester City)
While the improvements made by the likes of John Stones and Raheem Sterling were to be expected under Guardiola's tutelage, Otamendi has been a revelation. A hot-headed liability during his first two seasons in Manchester, the Argentina international's play in possession has improved beyond all recognition and his combative defending is all the better for occurring far less frequently on the seat of his pants.
Ashley Young (Manchester United)
A close call between two men who would probably sooner not be playing full-back at all, Young edges out fellow former Aston Villa man Fabian Delph. The latter's transformation has been classic Guardiola, applying his midfield nous in an assured take on his new role. Young is slightly more natural in the position, however, and his England recall is one of the season's unexpected individual achievements. Maybe tellingly for United this weekend, the 32-year-old's set-pieces are firing again.
Fernandinho (Manchester City)
Nemanja Matic has been hailed as one of the signings of the season and not without good reason. The former Chelsea man has brought power and poise to the base of the midfield in exactly the manner Mourinho required. Guardiola found archetype in Fernandinho at the Etihad Stadium and the Brazilian is one of the Premier League's most persistently underrated players. Combining a tireless workrate with sound technique and tactical and positional intelligence, he is his manager's dream. The flying machine that is the Manchester City attack would not function without Fernandinho directing traffic in midfield.
Kevin De Bruyne (Manchester City)
A frontrunner for the end-of-season gongs in England, De Bruyne has been simply sublime this season. Equally at home going through his full repertoire against an over-matched opponents as he is producing game-breaking goals and assists when faced by the elite, the Belgium star is a truly force-of-nature footballer.
David Silva (Manchester City)
Affectionately nicknamed "El Mago" (Spanish for "the magician") at City, World Cup winner and two-time European champion Silva has a legitimate claim to being the club's greatest ever player. It has been no surprise to see him excel under Guardiola but a delight to witness regardless. "There are players who are powerful, quick, strong, but they don't do what Silva does," former team-mate Nolito told the Guardian last month. "They can’t move as if the ball's tied to their boot."
Raheem Sterling (Manchester City)
Much like his initial season in sky blue under Manuel Pellegrini, Sterling's promising star faded last time around. As Bernardo Silva arrived and City pursued Alexis Sanchez, it was easy to envisage a future with him surplus to requirements at the Etihad Stadium. But Guardiola stood bullishly by the youngster's talent and has been rewarded in spades so far this term. With 13 goals in all competitions – helped by a penchant for dramatic late winners – Sterling is City's top scorer.
Leroy Sane (Manchester City)
Sane started the season out of the City side, with Guardiola reporting an underwhelming pre-season. It is now difficult to imagine them hitting top form without the lavishly gifted young German involved. The sight of Sane and Sterling operating in tandem will give United food for thought over what might happen if Mourinho played Marcus Rashford and Anthony Martial together on a regular basis.
Sergio Aguero (Manchester City)
With Romelu Lukaku's early-season goal glut a fading memory and Gabriel Jesus showing only flashes of his best form, this is an unexpectedly tricky spot to fill. Aguero's last goal from open play came on November 1 but the Argentina striker has 11 in all competitions this season, while eight versus United underlines an impeccable derby day pedigree.
FINAL SCORE: Manchester United 4 Manchester City 7