We conceded a 94th-minute goal to lose on the road at Brighton in a match overshadowed by what looked to be a serious injury to Bernd Leno.
Our goalkeeper went down after claiming a ball on the edge of the area, and immediately looked in trouble. After lengthy treatment, he was stretchered off with his right leg in a brace.
It was another frustrating moment for Mikel Arteta, just days after losing Pablo Mari and Granit Xhaka, in a game where he was looking for a response from his side.
We started much the brighter of the two sides with Pierre-Emerick Aubameyang having two early sights of goal before Bukayo Saka hit the bar with a brilliant curling effort.
Alex Lacazette was next to try his luck but a last-ditch block by Dan Burn kept out his low drive, and the French striker had another opportunity just after the half-hour mark but Mat Ryan made a fine save to keep out his goalbound header.
We were on top but with 10 minutes remaining in the first half, Bernd Leno went up with Neal Maupay to claim a high ball on the edge of the area and landed awkwardly and that was the end of his involvement.
His replacement, Emi Martinez, was immediately called into action to make a fine low save to hold Aaron Mooy’s fierce drive, before Aubameyang was denied in the area by a fine tackle by Adam Webster after combining nicely with Lacazette.
We started the second half much as we ended the first, with Aubameyang testing Ryan within a couple of minutes with a left-footed drive from the edge of the area.
Our captain soon had the ball in the net after being played through by Saka, but the flag had gone up – and after a VAR check the decision to disallow it was upheld.
Martinez then had to make a smart save at his near post from Maupay, before Aubameyang tested Ryan again at the other end with a firm shot.
We needed a breakthrough, and with 68 minutes remaining we got it when Saka found Pepe to the right of the area, and the Ivorian cut back on to his left and curled a superb strike into the far corner.
But Brighton hit back when, after a quickly taken short corner, Lewis Dunk forced the ball over the line from close range.
Now we had to react again, and Aubameyang soon saw a dipping shot saved by Ryan, before having another strike deflected behind moments later and then Shkodran Mustafi had a header saved.
But there was no way through, and in the fourth minute of injury time, Maupay slotted it past Martinez to condemn us to defeat.
HOW IT HAPPENED
WHAT IT MEANS
We have a five-day break now before we are next in action, when we head to the south coast again to take on Southampton at St Mary’s.
A fourth consecutive away game then follows, as we travel north to take on Sheffield United in the quarter-finals of the Emirates FA Cup.
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