Liverpool’s 5-0 win over Porto on Wednesday night was a statement victory.
Widely regarded as a tricky tie, it was expected that Liverpool would struggle to impose their usual game in the away leg. Despite being favourites, there was even a sense this could be a banana skin - especially as all around the team were potential causes of concern.
Liverpool are far from this finished product: Loris Karius has finally got a good run of form behind him but it will take time before he instils confidence - similar to Dejan Lovren.
Elsewhere on the field, Virgil van Dijk is still adapting and, whilst despite the fullback pairing of Trent Alexander-Arnold and Andrew Robertson looking assured thus far, knockout Champions League football would be a significant new test for the young players.
Lacking the suspended Emre Can in midfield, it had been a long time since Jordan Henderson and James Milner demonstrated their capability at the highest level, whilst Georginio Wijnaldum still has question marks when playing away from Anfield.
Their opponents on the night, Porto, will likely be Portuguese Champions and navigated a difficult and open Champions League group ahead of RB Leipzig and Monaco. They had only lost two of their last 45 games at home and boast the best defensive record in Portugal this season.
Any concerns were emphatically allayed.
James Milner put in his best performance in years, a masterclass in box-to-box midfield play. Henderson’s tenacity helped set the tempo of the game.
Finally, there looks a degree of impermeability to Liverpool’s defence, and the front three of Salah, Mane and Firmino’s are implausibly looking better as the season progresses.
Both the quality of the performance and the accomplishment of the result cannot be overstated. It was a display that will have perturbed the powerhouses of European football.
With a five-goal advantage, Liverpool are effectively into the last eight of the competition. Such a point characterises how they’ll be tested going forward.
Reaching the top
With the exception of whoever wins between Shakhtar Donetsk and Roma, the remaining teams will be at the elite level. This could play into Jurgen Klopp’s hands.
Liverpool’s most frustrating results this season have been against teams that sit back and defend with a deep block - the shock 1-0 defeat to Swansea, both a league 0-0 and cup exit to West Brom, and the 1-1 draw against Sam Allardyce’s Everton. The departure of Philippe Coutinho exacerbates the issue as he was key to unlocking space.
Liverpool’s undoing in Europe might have been against a team that deployed such an approach but they have now bypassed the stage where a lesser team would do so. Many of the teams Liverpool could face in the quarter-finals would try take the game to them - think PSG or Real Madrid, Barcelona, Manchester City.
These are all, of course, exceptional teams who would be considered favourites but there is potential, with how rapid and ruthless their forward line is, for Liverpool to exploit any space left and take a major scalp.
Even if Liverpool were to face a team that deployed such a defensive approach - for example, Jose Mourinho’s Manchester United - it would not necessarily be successful.
Should the opposition succeed in establishing a tight match, they wouldn’t necessarily be any more likely to break or capitalise on a mistake than Liverpool would be in breaking through.
Top six success
Given how well the other English teams have also done, it’s somewhat likely Liverpool meet another Premier League team.
Spurs and Manchester City have inflicted two of Liverpool’s three league defeats this season but Liverpool have also shown themselves capable of giving them a contest - being the only team to beat City this season as well as being only seconds away from beating Spurs.
Going further back, Klopp has a favourable record against top six teams. Two wins, four draws and a loss against Pochettino’s Spurs and unbeaten against Chelsea (two wins, three draws), whilst beating Manchester City on four occasions.
At the helm at Liverpool, he’s already knocked Manchester United out of European Competition in the Europa League in 2016. The three matches since Jose Mourinho took over have ended in draws.
There are other threats, of course. Shakhtar Donetsk or Roma could prove difficult - Shakhtar Donetsk performed well against Manchester City in the group stage and Roma have been out of form lately although Di Francesco should have them well-drilled for any such an encounter. Liverpool would be expected to have enough against either though.
Bayern Munich would probably represent the team that would cause Liverpool the most problems. They have won all but one of the games since Jupp Heynckes returned, and their unassailable lead in the Bundesliga will allow the veteran manager to keep his stars rested and fresh for the knockouts.
Bayern are also more accustomed than others with dealing with an aggressive pressing approach - a testament to Klopp’s influence in Germany, after other coaches and teams have emulated his Borussia Dortmund team.
There will be a lot of exceptional teams in the quarter-finals of the Champions League this season. But if Liverpool can fire on all cylinders - keeping the fluency of their front three, the aggressive pressing in the middle while seeing the investment in Van Dijk paying dividends at the back - they will consider themselves a match for any team.
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