Liverpool welcome Real Madrid to Anfield on Tuesday in the Champions League round of 16, and the latest meeting of Jurgen Klopp and Carlo Ancelotti.

Their respective histories could have been so different.

After Everton and Liverpool had played out a 1-1 draw at Goodison Park in October 2015, in the Sky Sports studio, Thierry Henry reached across and placed his hand on a bewildered Jamie Carragher's knee as the news was announced that Brendan Rodgers had been dismissed as Reds manager.

Within minutes, the favourites for the role were being discussed, with frontrunner Klopp ultimately being the man to come in and take the club back to the summit of English and European football.

The second favourite had been Ancelotti, out of work at the time following his exit from his first spell at Madrid, and Carragher argued that while the Italian had the more impressive CV, Klopp was the more suitable choice for the Anfield hotseat after his success at Borussia Dortmund.

"I think with either of those coming to Liverpool, the supporters would be ecstatic," he said at the time. "If it was me, I would go for Klopp ahead of Ancelotti. I think he's got more to prove. Ancelotti is a great manager of course, but he's gone to clubs where you would expect to win trophies.

"It's a difficult job now at Liverpool getting them back into the top four. Forget talking about the title. And I think it needs someone with that energy and drive to get Liverpool back to where it wants to be and I think Jurgen Klopp's that man."

Of course, Carragher proved to be right about Klopp.

It will never be known what would have happened had Ancelotti been hired instead, but he has gone on to enjoy success at other clubs since, with spells at Bayern Munich, Napoli and Everton before heading back to the Santiago Bernabeu in December 2021.

The two have faced off numerous times in opposing dugouts, with the upcoming two-legged Champions League tie set to be their 12th and 13th meetings.

It is interesting how frequently Klopp and Ancelotti have come up against one another, especially considering the Italian's 18-month spell at Everton was the only time they have managed in the same league.

They clashed on four occasions in Merseyside derbies – coincidentally after that had been the fixture that led to their names being linked with the Liverpool job back in 2015 – with two draws at Goodison Park in the Premier League and a 1-0 Liverpool win in an FA Cup third round game at Anfield.

The most notable encounter also came at Anfield in February 2021, with no fans in due to COVID-19 restrictions, where Ancelotti masterminded Everton's first win at the home of their neighbours since the turn of the century.

Their other seven meetings have come in the Champions League, Klopp coming up against Ancelotti for the first time during his penultimate season at Borussia Dortmund as they took on Madrid in the last eight, losing 3-0 in the Spanish capital before a spirited but unsuccessful 2-0 reverse back in Dortmund.

Two goals from Marco Reus in the first half had given the German side hope of a comeback, but Ancelotti's men put up the defences and managed to see the game out, a tactic that the Los Blancos head coach has used to good effect against Klopp on numerous occasions since.

He also frustrated Klopp in their first meeting as Liverpool and Napoli bosses respectively, with the Serie A side winning 1-0 at home in the 2018-19 group stage, restricting the Reds to just four shots – none on which were on target – as Lorenzo Insigne struck a late winner.

A Mohamed Salah goal in the reverse fixture was enough to send Liverpool through to the knockout stage with a 1-0 win at Anfield at Napoli's expense, with the Reds going on to lift the trophy in Madrid that season.

The two teams were drawn together again in the group stage the following year, with Napoli again defeating Liverpool in Naples, 2-0 this time, while they played out a 1-1 draw back on Merseyside.

Klopp and Ancelotti would not meet again in the Champions League until after their brief Merseyside derby rivalry, somewhat appropriately in the final as Liverpool faced Madrid in Paris last season.

While the game was heavily distracted by the chaos outside prior to kick-off that an independent investigation has since claimed was the fault of UEFA and the French authorities, on the pitch it had a feel of Klopp's previous struggles with Ancelotti.

Liverpool dominated large parts of the contest, but Madrid were largely able to contain them, though goalkeeper Thibaut Courtois still had to put in an outstanding performance to keep a clean sheet.

Ancelotti suggested after the 1-0 win thanks to a Vinicius Junior goal that Klopp's team were "more decipherable" than others he had faced, but ahead of their next clash, the German coach lavished praise on his opposite number.

"Carlo is the most relaxed manager I ever met in my life," Klopp said at his pre-match press conference. "One of the best people you can meet, fantastic person, a humble person, super smart and nice, and obviously his man management is at a completely different level to all of us, and I respect that a lot and admire it a lot."

Ancelotti reciprocated at his press conference, saying: "I have a good relationship with Klopp. We stayed for a year and a half in Liverpool during the pandemic, and we used to text each other and exchange gifts. He's a really lovely person."

There is clear mutual respect there, strengthened by the duo's personal achievements as well as how difficult they both find games against one another.

Klopp's teams have only managed to find the net seven times against Ancelotti's in 11 games, despite having 153 shots, suggesting the former Milan, Chelsea and Paris Saint-Germain boss knows how to restrict them to low-quality chances.

Ancelotti has relied on his team's defensive solidity more often than not, and boasts the superior record with five wins to three defeats and three draws, but he has never been able to beat a Klopp team in an away game when fans have been in attendance, with a noisy Anfield on Tuesday a near certainty.

He surely takes slightly more pleasure in besting Liverpool than he does most other foes following one of his most painful defeats as a coach when his Milan side was beaten on penalties in the iconic 2005 Champions League final in Istanbul, despite leading 3-0 at half-time.

This season's final will also be in the Turkish capital, but at least one of Liverpool or Ancelotti will not be there this time.

Klopp v Ancelotti. Germany v Italy. Beard v eyebrow. It is one of the great modern coaching rivalries, and round 12 should be another fascinating contest.