Arsenal’s new penchant for picking up red cards had to catch up with them eventually. Mikel Arteta’s side finally surrendered their unbeaten start to the season after William Saliba was sent off – their third dismissal in their opening eight league matches – as Bournemouth celebrated a famous victory thanks to goals from substitutes Ryan Christie and Justin Kluivert.

It was an evening to savour for their manager, Andoni Iraola, who saw his enterprising team record their first win over a side in the top half of the table since beating Manchester United here in December. For it to come against Arteta – who grew up playing for the same youth team in San Sebastian – made it particularly sweet. But with Bukayo Saka having not made the trip to the south coast, Arsenal – who missed the chance to go top of the table with Liverpool and Manchester City not in action until Sunday – had looked short of inspiration even before Saliba’s red card swung the balance of the game and they were condemned to a first away defeat of 2024.

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Arteta admitted before kick-off that “there was no point pushing” Saka with games against Shakhtar Donetsk and Liverpool to come this week after he returned early from England duty due to a hamstring injury. Yet the Arsenal manager will be concerned with how his side struggled without their talisman and captain Martin Ødegaard.

Iraola acknowledged this week that while their expected goals data had indicated they should be fourth in the table, the onus is on his players to “become a more efficient team”. They made their intentions clear from the start here as Alex Scott and Marcus Tavernier were deployed in attacking roles supporting centre forward Evanilson and they took the game to the visitors. By contrast, Arsenal looked short of ideas and almost fell behind when David Raya was then fortunate that his wayward pass to Scott didn’t result in a goal as Antoine Semenyo blazed over from distance.

Iraola and Arteta spent the majority of the first half an hour cajoling on the edge of their technical areas. But the game suddenly came alive when Leandro Trossard inadvertently played the ball over his own defence and Saliba brought down Evanilson as the Brazilian raced through on goal. A red card looked to be the likely outcome, although the referee, Robert Jones, initially only cautioned the France defender. With PGMOL chief Howard Webb watching on from the stands, however, VAR thought differently and Saliba was given his marching orders that mean he will miss the meeting with Liverpool next weekend.

Mikel Merino came close to finding a breakthrough on his full debut after good work from Raheem Sterling before the England forward was sacrificed for Jakub Kiwior to shore things up at the back. Semenyo had already forced Raya into a good save at his near post by then and Tavernier should have opened the scoring from his cross after Raya had initially fumbled before recovering to block the shot. Meanwhile, Arsenal’s supporters made their disgruntlement known with several chants directed at Webb and their other perceived injustices.

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Semenyo should have done better with a golden chance that fell to him 90 seconds after the restart after a clever backheel from Milos Kerkez. But having already played the best part of 90 minutes with 10 men in the draws against Brighton and Manchester City earlier this season, at first Arsenal appeared comfortable in their rearguard action.

Any hopes of a breakthrough seemed destined to come down Arsenal’s right side as Dango Ouattara continued to cause Ben White problems. So it was a surprise to see him make way as Iraola made three changes just after the hour mark, while Gabriel Martinelli almost had an instant impact off the bench when his cross was cleared at the last minute by Marcos Senesi. Kepa Arrizabalaga’s heart must have been in his mouth when he passed the ball straight to Merino, only for the Bournemouth goalkeeper to redeem himself by saving Martinelli’s shot.

It was from their next attack that Bournemouth finally found what they had been looking for. Kluivert’s clever flick following a short corner from Lewis Cook allowed Christie to apply the finish with aplomb. Semenyo could have doubled their lead after Arsenal failed to clear another corner but could not direct his shot on target. They didn’t have to wait long though as an underhit backpass from Kiwior led to Raya bringing down Evanilson inside the area and Kluivert stepped up from the spot to leave Arsenal to lick their wounds.