Barcelona will slug it out with off Liverpool in a mouth-watering Champions League tie later tonight.
 Here are 5 key battles that might shape the course of the game.
Messi vs Van Dijk
Virgil van Dijk has 25 clean sheets in 45 games for Liverpool this season, but he faces his sternest test yet when he comes up against Lionel Messi in his own backyard on Wednesday night.
The Dutch centre-back was crowned PFA Player of the Year this week, becoming the first defender to earn the award since John Terry in 2005, and Van Dijk will need to emulate the former England captain on Wednesday evening if Liverpool are to succeed in silencing the Catalan crowd; Terry was able to prevent Messi from scoring against Chelsea in all eight games that he played against Barcelona.
Messi has been deployed out wide for Barca in most games this season, but expect him to cut inside often on Wednesday night, or even drift into midfield before driving at Liverpool’s central defence
The fans at the Nou Camp will be in a confident mood after Barca secured a fourth La Liga title in five years on Saturday, but Ernesto Valverde’s side have been criticised for being too reliant on Messi this season. The Argentine forward has 46 goals and 22 assists in 45 appearances in all competitions, so if Van Dijk can stop Messi, the rest of the result may take care of itself for Liverpool.
Jordi Alba vs Mohamad Salah
Mohamed Salah has hit a rich vein of form at exactly the right time for Liverpool.
His double past Huddersfield made it five goals in the last six games for the Egyptian while also registering a club record – Salah’s 69 for the Reds in total is the most any player has notched in their first 100 matches.
And the No.11 is set for an intriguing battle of attrition at Camp Nou on Wednesday when he goes up against Spain left-back Jordi Alba, now in his seventh season at Barcelona.
Smart in possession and always keen to break forward and support attacks, no teammate can better his four assists in the Champions League this term and the 30-year-old has also chipped in with one goal.
The chief source of crosses for Valverde’s men with 25 in the tournament, stifling Alba’s creative side and testing his defensive resolve will be priorities for Salah.
Only Steven Gerrard (30) has scored more goals for Liverpool in the Champions League than Salah, who has racked up 15 since joining the Reds in 2017.
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Fresh off the back of securing the La Liga title, Rakitic will be braced for an assault on the Champions League trophy now, in what will be his second continental title should he manage to secure it. The Croatian has embarrassed both of the two English teams he has come across this season in Manchester United and Spurs, but whether he manages to repeat his showing against Liverpool depends on the mercurial Gini Wijnaldum.
The Dutchman has been the only mainstay in Liverpool’s midfield this season – one of the ‘undroppables’ alongside the front three and coming up against Rakitic will be his toughest test yet. A midfield battle to savour!
Semedo vs Mane
Mane’s greatest attribute is his blistering pace, but Semedo is no slouch. If anyone can keep up with Liverpool’s Senegalese winger, it is Barcelona’s Portuguese right-back.
Semedo will be wary of Mane’s runs but should also be able to match them, and the 25-year-old will be supported defensively by Barca veteran Gerard Pique, who is having one of the best seasons of his career.
With Roberto Firmino’s inclusion in the Liverpool squad still in doubt, due to the Brazilian forward’s ankle injury, it is vital that Mane steps up for Klopp’s team. The 27-year-old has frequently demonstrated his ability to score in the biggest games for Liverpool, but he will need to be absolutely clinical at the Nou Camp.
Should Divock Origi or Daniel Sturridge start in Firmino’s place, they will need to help Mane by occupying Pique and allowing the Senegal international opportunities to cut inside and test Semedo’s defensive nous, rather than just his pace.
Allison vs Luis Suarez
One of the best goalkeepers in Europe this season, Allison’s imperious form in front of goal is what has separated the Reds from defeat at times. The Brazilian, who moved to Anfield from Roma last summer, has kept seventeen clean sheets in the Premier League, the most in the competition.
Luis Suarez, on the other hand, has had a disastrous run in Europe – with Messi largely running the show from behind. A former Anfield darling, Suarez will no doubt be licking his lips at the prospect of scoring against his former employees, despite the mutual respect on both sides.