Benitez and Mourinho's sides went head-to-head time and again.
The two sides have shared some classic encounters down the years, especially in the past decade.
Their rivalry was ignited upon the appointments of Iberian duo Rafa Benitez and Jose Mourinho in the summer of 2004.
The Spaniard and Portuguese manager's lined up an incredible 16 times from 2004 to 2007; meeting in FA Cup semi-finals, League Cup finals, Champions League group stages, quarter-finals and semi-finals.
Mourinho had the better of the duels overall via a superior Premier League record against Rafa's Reds, but Benitez got the best of his foe in cup competitions.
Overall, Mourinho won seven times, Benitez won five, and there were four draws. Mourinho's Chelsea scored 16 goals and Benitez's Liverpool scored 12 (stats via Manuel Traquete for B/R).
Of course, there were many classic meetings before then and since; here's 20 of the best Chelsea vs. Liverpool encounters.
Chelsea 4-4 Liverpool (agg: 7-5)
This Champions League quarter-final, second leg is ranked as a UEFA Classic, Liverpool refusing to give up against Guus Hiddink's side after suffering a 3-1 defeat at Anfield in the first-leg.
Fabio Aurelio's clever free-kick and Xabi Alonso's penalty had given Liverpool a 2-0 lead at half-time but that man Drogba once again turned the game after the break.
Drogba made it 2-1, Alex's ferocious free-kick levelled the score on the night, Lampard gave Chelsea the lead—only for two goals from Lucas and Dirk Kuyt inside two minutes to restore Liverpool's lead.
Another from Lampard in the final minute equalled it up again and Chelsea progressed 7-5 on aggregate.
Chelsea 0-1 Liverpool
Liverpool secured their first League and FA Cup double in 1986 in Kenny Dalglish's first season as player-manager.
They clinched the first part of the double on the final day of the season—at Stamford Bridge, with Dalglish himself netting the famous title-winning goal.
Dalglish chested down Jim Beglin's clever dink down the inside-left channel and guided it past Tony Godden, as described by The Guardian.
Liverpool 0-2 Chelsea
Steven Gerrard's backpass allowed Didier Drogba to open the scoring as Chelsea moved to the brink of the Premier League title.
A year earlier, Liverpool had achieved their best ever Premier League finish, ending up runners-up to Man United. This result left them languishing in seventh and this match proved to be Rafa Benitez's last match in charge at Anfield.
Chelsea 1-2 Liverpool
A fresh and lively Liverpool side turned over Mourinho's expensively assembled squad at the Millennium Stadium.
The match will be remembered for John Arne Riise's stunning solo goal, collecting the ball deep inside his own half, dribbling half the length of the pitch before unleashing a thunderous strike past Carlo Cudicini.
Andriy Shevchenko levelled the scores before Peter Crouch nodded in the winner with 10 minutes remaining.
Chelsea 1-2 Liverpool
As the battle between Mourinho and Benitez continued, Liverpool again got the better of Chelsea in a cup match—progressing to the final where they'd beat West Ham on penalties.
John Arne Riise and Luis Garcia scored two excellent goals for the Reds at Old Trafford, before Didier Drogba halved the deficit late on.
Chelsea 2-1 Liverpool
The idea of a Champions League play-off match may be an exciting one and this was essentially that.
The final game of the season saw both sides level on points in a match that would decide who finished fourth in the Premier League.
Sami Hyypia's early header put Liverpool on the path to victory, but Marcel Desailly levelled things up within two minutes and Jesper Gronkjaer's goal proved the winner—leaving Liverpool fifth and putting Chelsea into Europe's elite competition.
The result led to Roman Abramovich purchasing Chelsea and changing the course of history.
Chelsea 0-1 Liverpool
Liverpool demonstrated their title credentials by ending Chelsea's 86-game unbeaten run in the Premier League at Stamford Bridge and moved three points clear at the top of the table, as reported by BBC Sport.
Xabi Alonso's deflected 10th-minute goal gave Liverpool victory and shattered a Chelsea sequence stretching back to February 2004 on home turf.
Benitez's side went on to finish second, achieving their highest Premier League points total in the process.
Chelsea 4-2 Liverpool
The Mark Hughes show. Liverpool were cruising, 2-0 up at half-time courtesy of goals from Robbie Fowler and Stan Collymore in this FA Cup fourth round tie.
Hughes was a half-time sub that changed the game. The Welshman scored the first himself before Gianfranco Zola equalised and Gianluca Vialli added two to give the Blues victory against a shell-shocked Liverpool side, bullied by Hughes' physical presence.
Chelsea went on to win the cup.
Liverpool 2-3 Chelsea
The match that really kicked off the battle between Benitez and Mourinho.
John Arne Riise, who was acquiring a taste for scoring against Chelsea, opened the scoring with a thunderous volley inside the opening minute.
But Steven Gerrard's headed own-goal with 10 minutes remaining sent the match into extra time—where Drogba and Mateja Kezman gave Chelsea the victory despite Antonio Nunez's efforts as he made it 3-2.
Liverpool won the League the following season.
Liverpool 2-0 Chelsea
Bill Shankly's Liverpool got the better of their London rivals and went on to lift their first FA Cup in the final.
Chelsea were the fashionable side with Terry Venables, Peter Bonetti, Eddie McCreadie, Bobby Tambling and Ron Harris.
Liverpool triumphed though with a wily display, as described by The Guaridan. A Peter Thompson solo effort and a Willie Stevenson penalty (the only spot kick he took for the club) the only goals of the game.
Chelsea 4-0 Liverpool
Liverpool's Stamford Bridge jinx continued with a rout as Chelsea inflicted the Reds' worst defeat in nine years.
Sam Dalla Bona—who?—was even on the scoresheet, grabbing the third as Jimmy Floyd Hasselbaink once again gave Liverpool's defence nightmares.
Graeme Le Saux opened the scoring after just three minutes, while Hasselbaink added the second before Eidur Gudjohnsen compounded the Merseysiders' misery in the final minute.
Liverpool 4-2 Chelsea
Much like Liverpool's Stamford Bridge jinx, Chelsea faced similar problems at Anfield in the 90s.
Patrik Berger scored a hat-trick and Robbie Fowler hit the fourth. Gianfranco Zola and Gustavo Poyet with the consolation goals for the visitors.
Liverpool 1-3 Chelsea
Chelsea broke their Anfield hoodoo to give them a commanding lead in this Champions League quarter-final—led by Branislav Ivanovic's two headed goals from corners.
Fernando Torres had given Liverpool the lead early on, but Ivanovic's goals were followed up by another for Drogba against Benitez's side.
This was Liverpool's only defeat of the season at Anfield.
The return leg proved a thriller, 4-4.
Chelsea 2-0 Liverpool
The match that saw Pepe Reina dismissed for his fracas with Arjen Robben—the Spaniard furious with the Dutchman's theatrics.
"Robben is a big actor and he did well enough to win an Oscar," Reina said, as quoted by The Daily Mail.
William Gallas and Hernan Crespo scored the goals for Mourinho's side.
Liverpool 5-1 Chelsea
Another humbling for Chelsea on Merseyside, inspired by new signing Patrik Berger. The Czech scored twice as Robbie Fowler, John Barnes and Andy Myers' own goal gave Liverpool victory.
Frank Leboeuf's late penalty for the visitors was a mere consolation.
Liverpool 1-4 Chelsea
Didier Drogba was often Liverpool's tormentor in these meetings and certainly was in this Premier League tie—with the home side suffering their worst home defeat in the League since a 1-4 loss on 13 December 1969 vs. Manchester United.
Frank Lampard, Damien Duff, Joe Cole and Geremi were the scorers, but Drogba assisted three of them and gave Liverpool a torrid afternoon.
The result put Chelsea a massive 17 points ahead of Liverpool—in October.
Liverpool 2-0 Chelsea
Roy Hodgson's short-lived Liverpool reign had few high-points; this victory over Carlo Ancelotti's side being pretty much the only one.
Hodgson's decision to pair Fernando Torres alongside Dirk Kuyt in a 4-4-2 formation was described as "bold by modern standards" in The Guardian match report from the day.
Torres was struggling for form since the World Cup but grabbed two first-half strikes to give Liverpool the three points—one of his final acts as a Liverpool player.
Chelsea 2-1 Liverpool
Drogba was, again, Liverpool's tormentor—scoring the winning goal.
His goal made it 2-0 after Ramires had given the Londonders the lead, but Andy Carroll's impact from the bench almost put Liverpool back into it, halving the deficit with a powerful finish.
Roberto Di Matteo's side added Champions League success shortly after.
Liverpool 1-0 Chelsea
The one that still riles Mourinho to this day—although, his rationale is somewhat flawed.
Mourinho claims Luis Garcia's goal wasn't over the line, but forgets to recall that had the referee not given the goal, Chelsea would have had Petr Cech sent-off, down to 10 men for 86 minutes and still have conceded a penalty.
Liverpool qualified for their first European Cup final in 20 years and cue years of chants of 'Where were you in Istanbul?'