Liverpool will face Barcelona in the semi-finals of the Champions League after beating Porto.

Here, Press Association Sport looks ahead to the clash with the Catalan giants.

Key Players

You have probably heard of Lionel Messi. We can leave the debate about whether he is the greatest player to ever play the game for another time, but the Barcelona forward is certainly in the conversation. His double against Manchester United in the quarter-finals took him to 24 Champions League goals against English opposition – twice as many as any other player, so we can only wish the Liverpool defence the best of luck. The problem for opponents is that the Argentinian forms only part of an intimidating Barca attack, which also includes Liverpool old boys Luis Suarez and Philippe Coutinho, plus French winger Ousmane Dembele. Further back Arthur is maturing into an outstanding midfielder alongside Sergio Busquets, while Gerard Pique anchors a solid defence.

Much like Barca, Liverpool's front three command the most attention, with Mohamed Salah, Sadio Mane and Roberto Firmino capable of terrifying any defence. But the key difference between last season's entertainers and this year's contenders is at the back, where goalkeeper Alisson Becker has added solidity behind Virgil Van Dijk.

Managers

With a nine-point cushion, Ernesto Valverde is well on course to deliver a second LaLiga title in as many years, following on from last season's league and cup double. But the 55-year-old's often conservative style of play has not received universal praise from the Barca faithful, and there is no question he could use a Champions League title to strengthen his position. Valverde signed a one-year contract extension in February, but whether he gets another one may depend on their progress in Europe.

Delivering a style of play that pleases fans has not been a problem for Liverpool's Jurgen Klopp, but the wait for silverware under the German is not over yet. There is every chance it will be within the next few weeks, however, which will only add to his already strong popularity on Merseyside and beyond.

Strengths and weaknesses

Weaknesses are not easy to find in this Barcelona side, but if there is one it is that most of their key players – Messi, Suarez, Pique, Busquets – are now the wrong side of 30 and they no longer play with the same zip as they used to. Finding replacements from the famed academy has not proven easy, and expensive imports intended to plug the gaps have not always settled quickly or easily – something which goes for both of the most expensive, Coutinho and Dembele. Some of Valverde's more conservative tactics may be an admission they cannot dominate for 90 minutes in the way they once did.

You will be similarly hard-pressed to find a weakness in Klopp's Liverpool side. Shortcomings at the back have long since been addressed by the arrivals of first Van Dijk and then Alisson. If there is a complaint, it relates to squad depth. The Reds' first XI can match up to anyone, but if they suffer injuries or suspensions the second string, particularly in attack, is not as strong.

ga('create', 'UA-72310761-1', 'auto', {'name': 'pacontentapi'});
ga('pacontentapi.set', 'referrer', location.origin);
ga('pacontentapi.set', 'dimension1', 'By Press Association Sport staff');
ga('pacontentapi.set', 'dimension2', 'a9ec7a78-5a74-461b-90de-a7ebd7d794cc');
ga('pacontentapi.set', 'dimension3', 'paservice:sport,paservice:sport:club-news,paservice:sport:football,paservice:sport:uk,paservice:sport:world');
ga('pacontentapi.set', 'dimension6', 'story');
ga('pacontentapi.set', 'dimension7', 'composite');
ga('pacontentapi.set', 'dimension8', null);
ga('pacontentapi.set', 'dimension9', 'sport:football');
ga('pacontentapi.send', 'pageview', { 'location': location.href, 'page': (location.pathname + location.search + location.hash), 'title': 'Here\u2019s how Liverpool and Barcelona compare before European battle'});