LIVERPOOL, England -- A stoppage-time winner, a clean sheet and the ability to overcome a physical challenge in a hostile environment: If there was ever an identikit performance to hammer out title credentials, Liverpool produced it against Everton at Goodison Park.
The eruption among away fans in the stands, following Sadio Mane's winning goal in stoppage time, summed up the importance of this victory. However, the passion did cross the line with three flares thrown onto the pitch from the Liverpool enclosure and three separate instances of supporters running onto the pitch.
But it was a high-octane atmosphere, one which saw Liverpool captain Jordan Henderson hugely fortunate to escape serious injury following a wild challenge by Ross Barkley, who earned a yellow card. Liverpool, though, held their nerve to collect three huge points in their pursuit of runaway leaders Chelsea.
Two weeks ago, Liverpool endured the pain now being experienced by Everton when they suffered a dramatic, stoppage-time defeat at Bournemouth, losing 4-3 after leading 3-1. But the resilience shown by Jurgen Klopp's players in responding to that setback has underlined their status as serious challengers to win the Premier League.
Chelsea will enjoy Christmas Day with a six-point lead at the top, and Antonio Conte's men will take some catching, but Liverpool are in the hunt. Klopp had no intention of playing down the significance of this victory at the end of the game.
"It was quite intense," Klopp said. "But I am very happy with a deserved win after a difficult game. We have only to win games. We cannot make a difference between the games because they are unbelievably close every week. But if you only win games when you are brilliant, you won't win many games. It was a battle and we were ready for it. It was how a derby should be."
Everton's forceful approach, which proved crucial to their 2-1 win at home to Arsenal last week, did not rattle Liverpool in the same manner as it unnerved Arsene Wenger's players. However, Klopp did admit his players needed 45 minutes to adjust to Everton's physical game plan.
"The plan of Everton was wild football," Klopp said. "They were chasing us everywhere in the first half, man-on-man orientated, and we couldn't handle it. But you have to play and let them run so they are no longer as compact. We let them run, then we played simple and quick, creating chances and we could have scored earlier. We scored right at the end, but I don't care when we score."
The acid test of any team's title prospects often arrives on occasions such as this. Goodison Park is a difficult place for any opponent to visit, with special intensity reserved for the red team on Merseyside, and Liverpool arrived with Koeman's team unbeaten on home turf in the league this season.
Everton may have been unconvincing since their bright start to the season faded, but Manchester United could not win here and neither could Arsenal, so the importance of this victory cannot be overstated from a Liverpool perspective.
In any title-chasing campaign, a win at Goodison is valuable currency, but it must be earned. Liverpool clinched a victory by suffocating Everton's supply line to Romelu Lukaku and fighting fire with fire when the heavy tackles came flying in.
Barkley's challenge on Henderson was by far the worst of the game, but Dejan Lovren was no saint during a tempestuous encounter, with Roberto Firmino proving his readiness to join in when the going got tough.
In the 69th minute, Barkley was fortunate to escape a red card for his foul on Henderson, a late, studs-up challenge that caught his England teammate just above the right ankle. Referee Mike Dean, though, inexplicably issued a yellow card.
Dean's assistant did not inform the referee of the challenge's severity, but Klopp was diplomatic when asked about the decision of the officials to allow Barkley to escape a sending off.
"It was a really harsh, harsh challenge," Klopp said. "I saw it one time, but everything is clear. If you saw it, say how it was. I think the referee had a difficult game, but maybe Ross was really lucky and Hendo was really lucky."
Henderson was quick to forgive Barkley -- "It was pretty late but I know Ross well, and I think he just mistimed it." -- but, as Klopp stated, the Liverpool man was lucky to not be badly injured.
The joy of victory will mask the pain of any bruises sustained by Henderson, though, with the former Sunderland midfielder now aiming to do what his predecessor Steven Gerrard failed to do: lift the Premier League trophy.
Liverpool are still outsiders when compared to Chelsea, and the New Year's Eve clash with Manchester City at Anfield will offer a true gauge of what Klopp's side hold in the chasing pack. However, the manner of their win at Everton means Liverpool must now be taken seriously as potential champions.