Liverpool’s 5-0 win against Watford on Wednesday was notable not only for keeping the Reds on top of the table, but also because it marked the first time in Premier League history that defenders had contributed five assists in a single match.
The source was the two full-backs; Trent Alexander-Arnold, with three, and Andy Robertson with the other two. If last season belonged to the front three of Mohamed Salah, Sadio Mane and Roberto Firmino, Liverpool’s ambitions in 2018-19 may well rely on the health and form of their left and right-backs.
The rise of full-backs as a key creative force has been a long time coming.
It’s always been a legitimate source of success when placed in the right hands - from marauders like Ashley Cole through to the precision delivery of someone like Leighton Baines - but a duo like Alexander-Arnold and Robertson are a rare beast.
Think of Liverpool’s goal away at Manchester City this season. A raking pass from the England international with his weaker left-foot to the Scotland captain inside City’s box, who knocks it across first time for Firmino to score. As full-back contribution goes, it was close to perfection.
Before this season no defender had ever assisted three times in a Premier League game; now it’s happened twice in less than 70 days (the other occasion being Kyle Walker-Peters for Tottenham against Bournemouth on Boxing Day).
Robertson's total of eight assists this season equals his club’s Premier League record by a defender - set by Stig Inge Bjornebye in 1996-97 - and the combined total of 17 this season is already more than in any previous Liverpool season in the Premier League era.
More significantly, each of Jurgen Klopp’s seasons at Anfield has seen an increase from the previous campaign. This isn’t random, it’s the steady progress of a distinct approach.
"It’s important," said Klopp ahead of the Merseyside derby when asked about the assists of his full-backs. "That’s modern football. If you ask a young boy 'what’s your favourite position?' I don’t think a lot of boys will say 'I want to be a full-back!'
"But football changed. They became much more important. I was a full-back myself for a decent part of my career, it looked completely different to what the boys are doing but at least I know the things to do; you have to be really strong defensively, but on the other side a lot of teams clear the wings for the full-backs offensively.
"You have to be able to be open-minded enough and clear enough to see some people in the box with the same shirt! That helps a lot. In that game [the 5-0 win over Watford] it was exceptional.
"I don’t think I was ever part of a game where somebody had a hat-trick of assists. It was special. He wanted the match ball, so he got it! It was really cool."
Remember the uproar in some quarters when Nathaniel Clyne was loaned to Bournemouth in January? A solid defender, yes, but just two assists in 77 appearances for Liverpool tells its own story. Not fit for purpose.
Just how highly should the Reds prize their full-backs? Very, is the answer. In the top five leagues this season, Liverpool are the only side to have two wide defenders with six or more assists.
Top creative full-backs in 2018-19
Bayern’s Joshua Kimmich leads the way, but he has played further forward on numerous occasions. Jordi Alba is there, of course, but he turns 30 later this month.
Robertson and Alexander-Arnold, in contrast, are 24 and 20 respectively and have years of service left in them, even if the younger man does eventually move into the central midfield role he has long been earmarked for.
Prioritising creativity from the full-back areas isn't just Liverpool's thing. Elsewhere in the Premier League, there's no better example than at Tottenham, whose full-backs have created 80 chances and provided 11 assists via Walker-Peters, Kieran Trippier, Danny Rose, Serge Aurier and Ben Davies.
None of them currently have the consistency of the Liverpool pair but for Mauricio Pochettino, as for Klopp, it is the system that is of greater importance than the personnel.
Even so, as Liverpool enter March with the Premier League title still in their hands, maintaining the fitness and sharpness of their two golden full-backs would seem to be the key to keeping their noses ahead of Manchester City.
The best full-back pairing in Europe? You won't hear any arguments from Anfield!