Jordi Alba Barcelona 2018-19Getty

VIDEO: Alisson, Jordi Alba - The Ones to Watch in UEFA Champions League

The second legs of the UEFA Champions League semi-finals take place this Tuesday and Wednesday, with four of Europe's most impressive sides vying for a place in the final on June 1.

Liverpool host Barcelona at Anfield knowing that just one goal from Lionel Messi and Co could curtail any hopes of progressing to the showpiece in Madrid, though in Alisson they possess one of the world's best goalkeepers.

Brazil's first-choice stopper has kept four clean sheets in Liverpool's five home UCL games, and he will need to be at his brilliant best if the Reds are to stage a miraculous comeback against Barca, who hold a 3-0 lead following the first leg.

Jordi Alba was instrumental in helping Barca earn their three-goal cushion - the Spaniard's wonderful pass set up Luis Suarez to open the scoring against his former side - and he will be hoping his influence proves crucial for Ernesto Valverde's men.

The adventurous defender has averaged 83 passes per game in this season's UCL; remarkable figures for a full-back.

Voting for Player of the Week opens on Thursday.

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