Manchester City inflicted a first league defeat of the season on title rivals Liverpool this evening courtesy of a 2-1 victory at the Etihad Stadium.
Sergio Aguero blasted the hosts into the lead five minutes before half time, only for Roberto Firmino to level things up for the league leaders shortly after the hour mark.
The champions responded within eight minutes, though, and Leroy Sane's pinpoint finish proved to be the winner as Pep Guardiola's side breathed new life into their title defence.
Find out how all of the action unfolded courtesy of Sports Mole's minute-by-minute updates below.
It promises to be a mouth-watering contest - and perhaps even a make-or-break one for Pep Guardiola's hosts, who are bidding to end an incredible run of form for their opponents.
There is plenty to look at before kickoff in an hour's time, so let's start by checking out the all-important team news...
Well, both managers make interesting calls, but we'll start with the home side and the first thing to note is that Kevin De Bruyne does not making the starting XI, despite returning to training after his recent muscle injury which kept him out of the win over Southampton.
The Belgian is deemed fit enough for the bench today, but Pep Guardiola has chosen not to throw him straight back in in a game of such intensity given his injury troubles this season.
There is a change further forward, however, as Leroy Sane replaces Riyad Mahrez in the starting lineup alongside Aguero and former Liverpool man Raheem Sterling.
Captain Vincent Kompany also starts for the second time in a matter of days, meaning that Stones replacing Zinchenko - who misses out entirely - is the second of two changes made by Guardiola from the win over Southampton.
The Argentine has a formidable record at home to Liverpool too, scoring in all six of his home league appearances against the Reds down the years. Another one today could prove to be one of the more valuable of his 250 in the leagues.
There is still the option of playing in that formation with the players selected, but we are more used to seeing each of Jordan Henderson, James Milner and Georginio Wijnaldum in a midfield two of three - rather than behind the striker - so there is the possibility that the Reds could be switching back to a 4-3-3 for this match.
Alisson comes up against his Brazilian compatriot and opposite number Ederson in goal today, while in defence the continued absences of Gomez and Matip mean that there was little option to switch things up even if Klopp had wanted too - although the performances of Alexander-Arnold, Lovren, Robertson and particular Van Dijk of late means that he probably wouldn't have anyway.
Roberto Firmino will be feeling particularly confident coming into this match having netted a hat-trick in his last outing against Arsenal on Saturday, although whether he will play in his newer number 10 role or as the central striker tonight remains to be seen.
He also has a good record against Manchester City having scored three goals and set up two more in his last four games against them in all competitions, so the prospect of coming to the Etihad is more likely to excite him than daunt him tonight.
Sadio Mane may not have as fond memories of this stadium having been sent off in the corresponding league fixture last season, although since then he has been on the winning side in the Champions League, of course.
Pep Guardiola's men only need a draw today to move back above Spurs into second, but they will know that only a win will really do considering the remarkable form Liverpool have shown so far this season.
It was the Christmas period which has left City in such a predicament, losing back-to-back matches against Crystal Palace and Leicester City while Liverpool continued their relentless winning run.
Pep Guardiola's side had not lost a league game to a team outside the established top six in almost two years before those results, but in those two games they dropped as many points as Liverpool having throughout the entire Premier League season so far.
So high are the standards now that successive loss can prove fatal to any title hopes.
The 27-point swing is more a reflection of how much Liverpool have improved rather than Man City losing their quality, but the champions are still 11 points worse off than at the same stage of last term. That said, their current tally would also have been enough to leave them top of the table after 20 games last season too, so the level of competition has significantly increased.
The champions are today looking for back-to-back wins for the first time in almost a month, while victory would also be their 100th under manager Pep Guardiola.
It just so happens that Klopp is something of a bogey opponent for Guardiola, though, with the German winning seven of their previous 15 meetings - more victories than any other manager has achieved against him. In home games against Klopp, Guardiola has a distinctly mixed record of two wins, two draws and two defeats.
Indeed, the champions have now conceded twice as many goals as their opponents this season, and after a run of six consecutive Premier League clean sheets, they come into this one having conceded in nine of their last 10 top-flight outings.
Indeed, after scoring three or more goals in just three of their opening 12 league games, Liverpool have since managed it six times in their last eight to silence suggestions once and for all that their attacking trio are failing to live up to last season's standards.
Only Chelsea's team of 2004-05 can match the stinginess of Liverpool's defence so far this term, having shipped only eight goals in their 20 league outings - half as many as the next meanest defence and a far cry from the recent days when their back line was considered their weakness.
The Brazilian went on to score a hat-trick as Liverpool swept a top-five rival aside in a 5-1 drubbing, with Sadio Mane and Mohamed Salah also on the scoresheet. A repeat against Man City may be unlikely, but the result would have boosted Liverpool's confidence even more as they made it nine wins on the bounce.
This time around the belief is once again growing on Merseyside that this could be their year to end the long title drought, and a victory today would leave them nine points clear of second-placed Tottenham and 10 above Man City with 17 games of the season remaining.
Indeed, this is only the ninth time that a team has reached the 20-game mark of a top-flight season without losing a game - Liverpool doing so twice - and you have to go back to Sheffield United in 1899-1900 for the last and only time a team failed to win the league from that position.
However, should Liverpool lose then the pressure will really begin to pile on their shoulders, and then it will be all about their reaction to the defeat. The Reds need only look at today's opponents for evidence of how costly back-to-back defeats can be in this title race.
The Reds could also do with improving their away record in these big matches having won just one such game in their last 10 attempts, although even a draw tonight will suit them much more than it will City. Liverpool have also won their last four league away games, conceding just once in the process, and are unbeaten in 10 so far this season.
Liverpool have proved in recent years that they can beat Man City - and win here at the Etihad too - but there is no getting away from the fact that City are still such a dangerous team. It is a match both sides will be going into looking to win - and it really could go either way - so we're going to have to sit on the fence and plump for a draw.
SPORTS MOLE SAYS: Man City 1-1 Liverpool
Indeed, it was more than an hour before either side had a shot on target in that match, although City did waste a golden chance to claim all three points - and perhaps change the course of the season - when Riyad Mahrez blazed a late penalty over the crossbar.
Liverpool have won seven of those, including their most recent visit to the Etihad Stadium, when they won 2-1 to secure their place in the semi-finals of the Champions League in April.
It was Liverpool who ended Man City's bid for Invincibility when they met in January last season, with the Reds running out 4-3 winners at Anfield to inflict a first league defeat of the campaign on the eventual champions.
MAN CITY STARTING XI: Ederson; Danilo, Stones, Kompany, Laporte; Bernardo, Fernandinho, Silva; Sterling, Aguero, Sane
LIVERPOOL STARTING XI: Alisson; Alexander-Arnold, Lovren, Van Dijk, Robertson; Henderson, Milner, Wijnaldum; Salah, Firmino, Mane
Stones then goes to clear the ball but smashes it straight at Ederson and the ball bounces back towards goal. It is centimetres away from crossing the line, but Stones recovers to hook it clear and it just goes under the foot of Salah on the line too.
They will not get closer than that!
HOW HAS THAT STAYED OUT?
Mane is played through by Salah, his effort hits the post and then it somehow stays out.
Watch live on Sky Sports PL & Main Event or follow here: https://t.co/AlaCpCXy8J pic.twitter.com/Bql8qDzoRP— Sky Sports Premier League (@SkySportsPL) January 3, 2019
The Argentine was appealing for a penalty seconds before, but picked himself up, collected a cross from the left and hammered it past Alisson. Goalkeepers should not usually be beaten at their near post, but there was such power behind that strike that it is hard to blame the Brazilian.
Both sides have had one big chance each, and the difference between the two sides so far is that Man City have taken theirs whereas Liverpool were 11 millimetres away from doing the same.
The Argentine got across Dejan Lovren but still had a lot to do as he collected Bernardo Silva's cross. However, he put such power behind his left-footed strike that even Alisson could not keep it out at the near post as it ripped into the roof of the net.
A slick team move initially released Mane, who slid his finish past Ederson but saw it come back off the post. Stones then blasted his clearance against Ederson before recovering to hook it off the line, with just 11 millimetres of the ball having not crossed it.
Somehow the clearance also avoided Salah on the line too, and Man City lived to fight another day after the closest of scares.
The Reds enjoyed spells in the ascendency during that opening 45 minutes and will be confident that they have the quality to get themselves level. A huge second half awaits!
37 - Most goals in Premier League matches between 'big six' clubs since the start of the 2011-12 season:— OptaJoe (@OptaJoe) January 3, 2019
37 Sergio Aguero
21 Harry Kane
20 Wayne Rooney
18 Robin van Persie
17 Eden Hazard
This one is all about the two full-backs, though, with Alexander-Arnold selling Sane a dummy before floating an inch-perfect cross to the back post with his weaker left foot. Danilo just cannot get his head on it, and Robertson steals in behind to play it back across goal, leaving Firmino with a simple finish from close range.
Sterling collects the ball on the right and brings it across the field before finding Sane in space, after Aguero had taken Alexander-Arnold away with a good run. From there it is all about the finish as he drills the ball past Alisson and in off the far post.
"Liverpool hit back!"— Sky Sports Premier League (@SkySportsPL) January 3, 2019
Wonderful full back play from both Alexander-Arnold and Robertson and Firmino heads home.
Watch live on Sky Sports PL & Main Event or follow here: https://t.co/AlaCpCXy8J pic.twitter.com/d5RrSYKvy0
26 - Leroy Sané has been directly involved in 26 goals (9 goals and 17 assists) in 25 league games at the Etihad Stadium since the beginning of last season. Sensation. #MCILIV pic.twitter.com/jMweM4HIJR— OptaJoe (@OptaJoe) January 3, 2019
The champions end Liverpool's unbeaten record in the league this season with a 2-1 victory courtesy of goals from Aguero and Sane either side of Roberto Firmino's equaliser. It was a match played at a frenetic pace from start to finish and Liverpool still enjoy a four-point lead at the top of the table, but today is Man City's day as they breathe new life into their hopes of retaining the title.
Thank you very much for joining Sports Mole for tonight's blockbuster clash as Manchester City inflict a first league defeat of the season on Liverpool to close the gap at the top of the table to four points. I will leave you with our match report, and be sure to stick around for reaction too.
From me, though, it is goodbye for now!