Positives & negatives from Arsenal's Champions League opener in Spain

Arsenal got their Champions League campaign off to a promising start against a high pressing and determined Athletic Club Bilbao in Spain tonight.

Goals from both second-half substitutes highlights Arsenal's strength in depth this season. The introduction of Leandro Trossard and Gabriel Martinelli enabled Arsenal to take all three points from an attritional encounter.

Athletic had the better of the opening exchanges, pinning Arsenal back with a high press and high defensive line. Camped in their own half and unable to settle on the ball, Arsenal conceded a number of free-kicks including one that saw Declan Rice go into the referee's book.

The Gunners struggled to beat both the press and the offside trap until the 20th minute when Noni Madueke got in behind and squared for Eberechi Eze who was too slow to react.

As the game opened up, Arsenal threatened on the counter attack. Viktor Gyökeres latched on to an early through ball but was forced wide before hitting a tame shot which Unai Simón fielded easily.

A few moments later Gyökeres almost converted a header from a Jurriën Timber cross but failed to direct his effort on target.

Robert Navarro came closest for Athletic Club when he crept in behind Zubimendi in the inside left channel. His shot was powerful but lacked direction.

Half-Time: Athletic Bilbao 0-0 Arsenal

Arsenal had the better of the early exchanges of the second half with Madueke beating Adama Boiro almost at will.

It wasn't until Martinelli replaced Eze on the left and Trossard came in for Gyökeres that Arsenal grabbed the game by the scruff of the neck. The two combined for Martinelli to score just 36 seconds after the Brazilian had entered the fray.

Then with less than five minutes to go, Martinelli returned the favour for Trossard to score.

Full-Time: Athletic Bilbao 0-2 Arsenal

Positives & negatives from Arsenal's Champions League opener

Positive #1: Arsenal were compact in defensive transitions

The decision to play Martin Zubimendi, Mikel Merino and Rice as a midfield trio paid off under intense early pressure from Athletic Club.

With Zubimendi in the pivot, Rice and Merino were able to play as traditional midfielders with Rice marginally deeper than the Spaniard.

Athletic Bilbao found it difficult to find spaces in the midfield third and Arsenal were able to work themselves into the game from a solid platform as a result. Rice was instrumental in breaking up the play while Zubimendi got the attacks going.

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