When Manchester City had the Premier League effectively stitched up by the halfway point of the competition, it was only inevitable that people would start heralding them as one of the best teams to grace the English top division.
From that point – again inevitably – Pep Guardiola’s side have hardly enjoyed the sort of success that many had suspected they might.
That doesn’t stop them from being in with a shout of being the best Premier League side ever, of course. But there are a number of reasons that stand against them.
Here are five of those reasons.
1 They aren't invincible
Ever since the foundation of the Premier League back in 1992, England's top-flight has produced some of the best teams in the history of football.
One such example is the Arsenal side that went the entire 2003-04 season unbeaten and have gone down in history as The Invincibles. In the end, they went a staggering 49 league games without losing a single match and are the only club to have won a special golden version of the Premier League trophy.
After the sensational start to Manchester City's 2017-18 campaign that saw the Citizens going unbeaten in all competitions until December, pundits and fans predicted that City could go all 38 league games with zero losses.
That was until their first trip to Anfield in January, when Liverpool bested their North West rivals 4-3, despite a late comeback for the away side. 20 games without an L on their record, very impressive but it's nowhere near the record that the Gunners still keep.
Some will argue that the amount of wins that the Sky Blues got in the last 12 months (an all-time record of 32 in a 38 game season) and their incredible achievement of being the first team to get a century of points in top-tier English football is more impressive. That's a valid opinion but Liverpool and Manchester United have proved that Manchester City aren't the undisputed best team in England for 2017-18.
Barcelona have recently showed how hard it is to go an entire league campaign unbeaten, losing to lowly Levante last week.
Throughout Europe, there are other examples of teams that have gone a domestic league campaign unbeaten: Arsenal are just one of two sides to have completed the run in England, the other being Preston North End all the way back in the 19th century. That means that none of the great Liverpool sides in the 70s and 80s achieved the feat, nor any of Manchester United's Ferguson teams.
To become an invincible side, you need to be one of the very best in history, something Pep Guardiola's Manchester City aren't.
2 They failed in Europe
Manchester City have won everything there is to win in England since their 2009 financial takeover but European silverware has so far eluded them.
Nottingham Forest, Aston Villa and cross-city rivals United have all lifted the biggest prize in World Football but none as are successful as Liverpool. The Reds have won the European Cup a British record five times in their illustrious history and Manchester City will look for similar success in the coming decades.
For now, though, the Citizens have had little luck in Europe, only going as far as the semi-finals once.
Dominating in the group stages and playing Basel off the park in the Round of 16 this season would suggest that their previous best of making the final four wouldn't last. However, the quarter-final draw same them come up against a Liverpool side who were one of just two sides to best the Sky Blues in the season.
Even so, Manchester City were the bookies' favourites and with good reason. Liverpool, though, had other ideas, blowing away Manchester City at Anfield with their deadly triad of Mohamed Salah, Roberto Firmino and Sadio Mane in the first half and were defensively solid during the second period.
The return leg at the Etihad threatened to spark into life when Gabriel Jesus netted virtually from the kick-off but Liverpool rallied once more with goals from Salah and Firmino sending the Manchester club out. That made it three defeats out of four games against the Reds, a huge blot on Guardiola's copybook this season.
3 They aren't treble winners
When Manchester City were romping away with the league in the early stages, there was genuine talk of a first-ever quadruple in English football.
That would mean winning the Premier League, League Cup, FA Cup and the Champions League all in one campaign, a mammoth task, but one that Guardiola's men seemed up for.
Even by March, everything was on track and a routine win against third-tier Wigan Athletic in the FA Cup would've seen them through to the quarterfinals.
However, the Latics threw up another cup upset, winning 1-0 at the DW Stadium despite the intense pressure they were under for almost the entire game.
That coupled with the aforementioned Champions League exit, meant the City won two trophies this campaign, fantastic by anybody's standards.
To be considered the best, though, the bar is set astronomically high, and when it comes to the best trophy winning club, look no further than Manchester United.
The Red Devils have won more silverware than any other English club, and their 1998-99 season has gone down in legend as one of the best ever.
When Teddy Sheringham tapped home Ole-Gunnar Solskjaer knockdown at the Camp Nou, Manchester United had completed the only treble in English football history. The Premier League, FA Cup and Champions League were all heading to Old Trafford, despite all the odds being against them.
Manchester City might match their rivals' feat one day but for now, all they can do is dream.
4 They have a bigger defence budget than Bosnia...
The spending in top-tier football, and in particular in the Premier League has been blown out of proportion, largely due to the Neymar transfer.
There's very little point looking back with rose-tinted glasses and pretend that money has never been a part of the game until recently, it always has.
The days of Celtic winning the European Cup with a squad born within 10 miles of the club are gone but there's something about the way Manchester City have won this title that makes it feel like it's bought, rather than earned.
After all, they have spent more money on defenders in the past twelve months than countries like Bosnia have spent on their national defence.
It runs deeper than that too, despite spending a quarter of a billion pounds on upgrading the club's youth and training facilities, nobody has graduated from City's academy into the first team.
Players like Phil Foden might make it in the future, but a lot of the same criticisms that are aimed at Chelsea can be applied to Manchester City too, there aren't any local lads in that starting XI unless an injury crisis hits.
5 They haven't maintained success... yet
For a good side to become a great side, the high standards that are set one season must be met again the next.
This season was no fluke, you don't win the league by nearly 20 points through luck but for this team to be considered alongside Mourinho's Chelsea and Ferguson's Manchester United they have to defend their title in 2019.
Manchester United hold the record with three consecutive Premier League titles, something they achieved twice, and that will be City's record to beat.
Recent history doesn't make good reading, though, as no side has successfully defended England's top division since 2009, almost a decade ago now.
Dynasties are formed over years, but with the funding and the quality-laden squad they already have, Manchester City can make their own in the seasons to come.
Do you think Manchester City are the best Premier League side ever? Let us know by commenting below.
Want to share your opinion? Why not Write For Us?