Barcelona vs Arsenal team news: Alex Iwobi and Mohamed Elneny start, Thomas Vermaelen on bench

A look at the sides for tonight's Champions League Round of 16 second leg

A view of the Nou Camp (GETTY IMAGES)

Laurent Koscielny returns to the Arsenal line-up for tonight's Champions League tie with Barcelona amid a raft of changes by Arsene Wenger from the first-leg.

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Following their 2-0 first-leg defeat, Arsenal must score twice at the Nou Camp tonight and win by a margin of two goals if they are to advance to the quarter-finals of the competition.

Koscielny has been out of action since the defeat to Manchester United at the end of February but is back in the side, as he was for the first-leg.

There are many other change. David Ospina starts in goal instead of Petr Cech while Gabriel plays in place of Per Mertesacker, who is on the bench. Mesut Ozil and Alexis Sanchez are the only midfield/attacking survivors from the first-leg. Aaron Ramsey, Francis Coquelin, Alex Oxlade-Chamberlain and Olivier Giroud are replaced by Mohamed Elneny, Mathieu Flamini, Alex Iwobi and Danny Welbeck in an experimental side.

Barcelona, who are bidding to become the first team to retain the trophy in the Champions League era, make just one change from the first-leg. Jeremy Mathieu comes in for the suspended Gerard Pique in the centre of defence. Former Arsenal captain Thomas Vermaelen is on the bench.

It means Lionel Messi, Luis Suarez and Neymar all start.

Barcelona team: Ter Stegen, Alves, Mascherano, Mathieu, Alba, Rakitic, Busquets, Iniesta, Messi, Suarez, Neymar

Arsenal team: Ospina, Bellerin, Koscielny, Gabriel, Monreal, Elneny, Flamini, Iwobi, Ozil, Sanchez, Welbeck