Arsenal moved three points above Manchester City at the top of the Premier League with a nervy 1-0 win over Newcastle.
Eberechi Eze scored the decisive goal with a stunning, ninth-minute strike from the edge of the box following a short corner routine but had to be taken off in the second half after going down off the ball.
His substitution, which he later said was only precautionary, followed the withdrawal of Kai Havertz in the first half, but Arsenal boss Mikel Arteta downplayed the severity of the injuries. "They are muscular niggles," he said. "We don't think it's too much."
Arsenal had been knocked off the Premier League summit when Manchester City beat Burnley on Wednesday and had to work hard to regain top spot despite Eze's early strike.
Their sloppiness allowed the out-of-form visitors to gain a foothold in the game and they had chances to equalise in an anxious finale for the home fans, with Yoane Wissa firing wastefully over after being played in on goal by fellow substitute Nick Woltemade.
Arsenal created little as they struggled to build any momentum after Eze's goal, only showing some improvement with the return of Bukayo Saka as a late substitute for his first appearance since last month's Carabao Cup final loss to Manchester City.
The England international sent a deflected effort narrowly wide soon after his introduction and also helped create an opening for Martin Odegaard, who was denied by Nick Pope.
Arsenal had earlier felt the Newcastle goalkeeper was fortunate to avoid a red card when he was only booked after rushing out of his goal and fouling Viktor Gyokeres as he chased a long pass.
Arsenal had other opportunities to kill the game as it entered seven minutes of stoppage time but their failure to do so allowed Newcastle to continue applying pressure.
They had another chance when Dan Burn headed straight at David Raya, who had earlier saved from Sandro Tonali.
The loss is Newcastle's fourth in a row in the Premier League as their poor season continues. Arsenal, meanwhile, are able to celebrate a return to the Premier League summit, albeit with injury concerns ahead of Wednesday's Champions League trip to Atletico Madrid.
Arsenal boss Mikel Arteta in his press conference: "I'm really happy for the win. We talked about game one and how important that was.
"We should have finished probably with a bigger margin in certain moments of the game, but when it's 1-0, it's always tough because they have quality. They brought so many good players from the bench as well.
"And when we don't finish the action, especially the open ones that we had, the margins are going to be smaller."
On the decision not to send of Pope, he added: "It's a clear red card. I've watched it 10 times. If you have ever played football, it's a red card.
"It's the second time in two games. We were up against Manchester City when Kai Havertz goes through and [Abdukodir] Khusanov fouled him at 1-1.
"The title is there. It is a red card, guys. So, these are the margins as well, and hopefully that's going to change."
Arsenal captain Martin Odegaard to Your Site: "It was tough. Very intense, very physical. Especially for me, playing 90 again was tough. But we did everything we could and we got the win.
"That was the most important thing and we did well to get over the line and get the three points."
On the short corner routine for Arsenal's goal, he added: "We practise it all - short ones, first balls, second balls, everything.
"That's our quality, we can score in so many different ways. Today we did it brilliantly, we were dangerous a few more times as well. Credit to the work we did on the training ground.
"The stadium was a bit annoyed we took it short a few times, but it paid off in the end and it was a brilliant finish from Ebz."
Your Site pundit Jamie Redknapp: "You can tell yourself all you like that pressure is a privilege. 'We are giving ourselves such an opportunity...'
"But actually, when you're out there, sometimes fear can strangle you. It can take over you, and all the simple things that normally you just do, because you've done it since you were 10, 11 years or age, you find it so difficult, and that's what's happening with Arsenal right now.
"Individual mistakes, all the players, maybe not having that final pass. And it just suffocates you. It stops you being the player that you are.
"And that's why it was so important today that there was one outstanding moment of real quality by Eze. That was the real difference, an absolutely incredible moment."
Newcastle boss Eddie Howe to Your Site: "We're in that moment where we're losing games even when we look stronger. We've got to be resilient and find a way.
"Today is a big step forward. We need to make sure that's not just attributed to the fact it's Arsenal away from home and the players are hyper-alert to make sure we perform.
"We have to make sure we have that for every game.
"But we have to take the positives and the performance and know that will ultimately change results."
