Manchester United's defeat in the FA Cup final ultimately meant that they finished the season trophyless.
Across the city, Pep Guardiola's centurions won the league by a mammoth 19 points. So, in short, Jose Mourinho has plenty of work to do this summer.
Former Red Devils goalkeeper Edwin van der Sar has now weighed in with his advice on what his old club need to do to bridge the gap.
It's easy enough to say that Ed Woodward needs to put his hand in his pocket and to be fair, midfielder Fred and full-back Diogo Dalot have already arrived at Old Trafford in the last fortnight.
Forking out millions will not necessarily be enough. In fact, the 20-time champions have spent over £380million since Mourinho took over from Louis van Gaal in 2016.
As Van der Sar has emphasised, the club do need to make signings, but they will need to be additions that fit with United's style and ethos.
"Maybe it's more difficult, now more money is coming into the game," the ex-Holland international said, via the Manchester Evening News.
"Others are also catching up a lot. Maybe richer owners are investing larger amounts of money into the squad.
"Hopefully United can catch up. [They] finished second, lost the FA Cup final. This year they need another two or three signings to stay a little bit more on that level with City than this year."
'A certain type of football'
United fans will particularly welcome his comments on the brand of football he would like to see at the Theatre of Dreams, with Mourinho's pedestrian, often negative style proving a major bone of contention.
"Of course in my area there's a certain type of football that you like to play but that depends on the manager," the former stopper added.
"I think the crowd wants also a type of footballer; let's hope with the signings he's making and the type of football they want to play at United, they can have some success."
In this summer's transfer market, it's been first blood to the red side of Manchester.
Yet, it's surely only a matter of time before Guardiola reaches for his chequebook and once that happens, United could have some more catching up to do.
What do United need to do to catch City? Have your say in the comments.