Arsenal forced to make late change for Champions League opener vs Athletic Club due to UEFA rule

Arsenal have been thrown a curveball ahead of their clash against Athletic Club. The Gunners will have a new look when they face Ernesto Valverde's squad at the San Mames Stadium on Tuesday evening for the opening round of the Champions League campaign.

Due to UEFA rules, Arsenal will wear their blue away shirt with a new pair of silver shorts and socks. When the north London outfit previously donned the strip during pre-season, they wore dark blue shorts and socks.

To avoid a kit clash with Athletic Club - whose home kit comprises a red and white striped shirt with black shorts - Arsenal have been forced to wear a different pair of shorts and socks. Article nine of UEFA's Equipment Regulations outlines that teams must be prepared to mix and match items in order to create a visible contrast with the other team.

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There is also an order of priority for the selection of colours for a match; home team outfield player attire, away team outfield player attire, home team goalkeeper attire, away team goalkeeper attire, then referee team attire.

UEFA adds: "If there is a clash for one of the above participants that can't be resolved (i.e. none of the approved attires offer the required level of colour contrast), then other participants may have to change (in reverse order) until a suitable contrast can be found."

If Donatas Rumšas, who will be officiating the match, believes that Athletic Club and Arsenal are wearing strips that could lead to confusion, the Spanish outfit, as the home team, must change their attire purely for practical reasons.

While the kit-man reacts to the late change, Arteta has been busy preparing to go the distance in the Champions League. Speaking to reporters at the Emirates Stadium on Saturday afternoon, the Gunners manager claimed that he made a conscious effort to bolster the squad depth.

Arsenal invested nearly £300m on new players in the summer transfer window without offloading too many big names. Arteta said: "The demands of the amount of games that the players have to play, they have to play 70 or 74 games throughout the season, it's never been done.

"When the intensity goes that high, they are not going to be able to sustain that. So you need more players, the standards have raised, we need better players, and there's no secret."

On returning to the north of Spain, where Arteta grew up, he said: "It doesn't matter what we talk about, what we want to do, it’s what we have to do. It's not what we want.

"We have to now work today again, review. There are a lot of things that we have to get better at to be able to score even more and be more dominant in certain phases of the game and go game by game.

"I'm now preparing to win in Bilbao which is going to be incredible. I hope you all go because it's one of the best places to go, north of Spain, that's where I'm from. I think you're going to enjoy it guys and an incredible stadium atmosphere to play football."