With each passing week and competition progression, the impossible seems that little bit more possible.
The suggestions that Liverpool could do the quadruple of Premier League, Champions League, FA Cup and Carabao Cup have been around ever since Chelsea's Kepa Arrizabalaga skied that penalty over the bar to confirm victory in the latter competition in late February, but they were usually given short shrift.
Manchester City had been on Merseyside a day before that Wembley final, when Phil Foden's late goal - and a late penalty reprieve - saw them beat Everton 1-0 to move six points clear of the Reds at the top of the table. Granted it wasn't quite the 14 point gap they enjoyed at the start of the year, but it looked to be enough.
Now that gap stands at a solitary point, and the Reds will go top if they avoid defeat at home to Manchester United on Tuesday.
Since winning the Carabao Cup they also advanced to the semi-finals of the Champions League and now the FA Cup final at City's expense. They have a minimum of 11 games left this season and a maximum of 12. It has to be said that 'it' is on because, well, it is.
United will be the latest team to try and stop the runaway train at Anfield on Tuesday, and although standards at that club have dipped dramatically since Sir Alex Ferguson's day, they of course have their own history of multiple trophy successes.
It is now almost 23 years since Fergie masterminded United's historic treble success of Premier League, FA Cup and Champions League, culminating in that remarkable win over Bayern Munich in Barcelona.
It is a period which rightly looms large in United's illustrious history, but they are sure to be concerned that great rivals Liverpool could surpass that three trophy feat in the coming weeks.
How do those two teams and their seasons compare though?
We've taken a look.
The teams
Goalkeeper and defence
Widely regarded as one of the best goalkeepers in the world in the 90s, Peter Schmeichel would play in 56 of United's 62 matches in all competitions in the treble season, during which he turned 35 years old.
The captain on that night in Barcelona, the Dane's age had begun to become a talking point over the campaign as United proved to be a little more leaky at the back than in previous years. They would win the league having conceded 37 goals, the most in the top four, with second placed Arsenal shipping just 17.
The Champions League final back four - Gary Neville, Ronny Johnsen, Jaap Stam and Denis Irwin - were the first choice quartet across the campaign, with David May, Phil Neville, Henning Berg and a young Wes Brown in reserve. Stam, the Dutch centre-back, was seen by many as the best defender in the world.
These days that honour probably goes to the Dutchman Virgil van Dijk, the jewel at the heart of the Liverpool defence which usually comprises Trent Alexander-Arnold and Andy Robertson raiding forward from full-back and one of Joel Matip or Ibrahima Konate next to Van Dijk, with Joe Gomez also in reserve.
In goal, Alisson will turn 30 this year and is at the peak of his powers.
Midfield
Fergie's 1999 team would relish the midfield battle, and they had plenty of star names in there to help win it.
Roy Keane and Paul Scholes were infamously both suspended from the Champions League final, with Nicky Butt and Jesper Blomqvist coming into the side along with star names David Beckham and Ryan Giggs.
Beckham's haul of 11 Premier League assists that season put him behind only Dennis Bergkamp and Jimmy Floyd Hasselbaink in that regard, and with Scholes (11) and Giggs (10) both hitting double figures for goals in all competitions, it was clear how the midfield contributed to the quest for honours.
Of course, Jurgen Klopp wants his midfield to play in a completely different way.
Fabinho is the top scorer in the department with seven goals, although three have been penalties, with Naby Keita, Jordan Henderson and Alex Oxlade-Chamberlain next on the list with three each - although the latter has also played in attack.
For Klopp, midfield is all about controlling space and maintaining shape, outworking the opposition and making the most of the marginal gains that are deemed much more important than in Ferguson's day.
His creativity comes from the wide areas, with full-backs Alexander-Arnold and Robertson contributing 33 assists between them, and from the increasing influence of the supremely gifted Thiago Alcantara.
Attack
Ferguson's options up front were apparent in the Champions League final, where Dwight Yorke and Andy Cole started before Teddy Sheringham and Ole Gunnar Solskjaer came off the bench to score.
Yorke was the side's top scorer that season with 29 in all competitions, followed by Cole on 24, Solskjaer on 18 and then Scholes and Giggs before Sheringham's five.
Sheringham had a taste for a big goal though, scoring as he did in the FA Cup final that season, and all four contributed at vital moments across the campaign.
It feels bizarre to state now, but Liverpool's striking options looked thin when Mohamed Salah (28 goals this season) and Sadio Mane (18) jetted off to the Africa Cup of Nations in January - eventually facing each other in the final a month later.
Many predicted that would be death knell for Liverpool's season, but this campaign has seen the real arrival of Diogo Jota as a top class forward.
The Portuguese has 21 goals, taking some of the scoring burden off Roberto Firmino who has 11.
The exciting Luis Diaz was added in January, and although he has only scored three times so far, he has contributed so much more than just goals.
Klopp now has an array of options, so much so that - perhaps bar the world star Salah - he could pick any three from five in attack for virtually any game.
The managers
Going into the 1998-99 season (the still unknighted) Ferguson had won four Premier League titles, three FA Cups, a League Cup and the European Cup Winners' Cup.
Having already achieved what he would come to explain was his greatest aim of "knocking Liverpool off their perch" in the preceding years, the Scot was coming to the halfway point of his glorious 27-year tenure at Old Trafford, and having amassed the second great team of that era he was primed to achieve success on three fronts.
After Liverpool had imploded it was Blackburn and Newcastle who had taken up the challenge of facing Ferguson's men head on in the title race, with Arsene Wenger's Arsenal emerging in the late '90s.
Ferguson cut a fearsome figure throughout that period, ruling with an iron fist and getting the most out of his players through a mixture of intimidation, instilling passion and acute tactical awareness.
Klopp probably doesn't get the credit he deserves for that latter quality, with the passionate side of the game and the energy of his team usually credited for his successes, which now include the Champions League, Premier League and League Cup.
Defeats in finals in the first few years of his tenure did lead some to question the German, but with a spellbound supporter base hanging off his every word and an often divided club more united than ever, Liverpool look a supremely confident outfit under his stewardship.
As the only club willing to take on the behemoth that has been Manchester City in recent years, Klopp and Liverpool's place at the top of the game is unquestioned.
The seasons
United's total of 79 points from their 38 league games in the treble season would undoubtedly see them finish a distant third behind Liverpool and City these days, but the game has changed.
Ferguson's side drew eight league matches before the turn of the year, but it was a run of nine wins in 10 - and a draw with Arsenal - which saw them get their noses in front in the title race, eventually pipping the Gunners by a point on the final day.
A week later they beat Newcastle in the FA Cup final at Wembley having eliminated Liverpool, Chelsea and Arsenal on the way, the latter pair via replays, while the Champions League was secured after they battled through a group that included Barcelona and Bayern Munich, before epic knockout wins against Inter Milan and Juventus and then the Bayern final.
In the League Cup, they were knocked out by eventual winners Tottenham in the quarter-finals.
Such is the relentless pace you need to set at the top of the table these days, Liverpool would have thought they were out of the title race by early January and a 2-2 draw at Chelsea - at a time when their record stood at played 20, won 13, drawn 6, lost 2.
They won 10 in a row after that before a draw with title rivals Manchester City, and the race looks like going to the wire.
In the cups, wins away at Norwich and Preston set up a Carabao Cup quarter-final with Leicester, which saw the Reds come from 2-0 and 3-1 down before winning on penalties, with Arsenal then beaten in the two-legged semi-final and Chelsea in the final in another shootout.
Shrewsbury, Cardiff, Norwich, Nottingham Forest and Manchester City have all been beaten in the FA Cup en route to the final, while after emerging from a tough Champions League group of Atletico Madrid, AC Milan and Porto, Inter and Benfica have been beaten in the Champions League ahead of next week's semi-final with Villarreal.
