The fretting over Arsenal's squad depth was supposed to end when the Premier League's summer transfer window closed on Friday.

Raheem Sterling's last-gasp arrival on loan from Chelsea had many Gunners supporters pitching up at Emirates Stadium on Saturday enthused by the options manager Mikel Arteta has at his disposal. Yet they left the ground after Saturday's 1-1 draw with Brighton & Hove Albion concerned about a midfield area that suddenly looks light ahead of the biggest week of the season by some distance.

First, there is an international break in which to draw breath and regain some of the composure that Arsenal temporarily lost here following Declan Rice's 50th-minute red card. But then comes a seven-day period in which they travel to Tottenham Hotspur for the north London derby, Italy for a Champions League opener against last season's Europa League winners Atalanta and then to Premier League champions Manchester City.

Right now, the indications are that new 32.5 million signing Mikel Merino will miss all three matches after suffering a fractured shoulder in his first training session. Rice is now suspended against Spurs after a controversial dismissal, the first of his 245-game league career.

After a strong tackle on Joël Veltman just before half-time, the pair tangled again shortly after the restart. As Veltman went to kick the ball -- a moving ball -- to restart play following a free kick in his favour, Rice nudged it away and Veltman, who had already started swinging his right leg, made contact with Rice instead of the ball.

The Premier League later clarified Rice had "delayed the restart," something he had technically done but in a manner not consistently punished; Brighton's João Pedro booted the ball away after it ran out in the first half with no sanction from referee Chris Kavanagh. Arteta also cited another first-half moment and claimed Veltman should have in fact been sent off for kicking Rice.

"I was amazed," Arteta said postmatch. "Amazed, amazed, amazed because of how inconsistent decisions can be.

"In the first half, there are two incidents and nothing happens. Then, in a non-critical area, the ball hits Declan [on the back of his leg], he turns around, he doesn't see the player coming and he touches the ball.

"By law, he can make that call, but then by law he needs to make the next call, which is red card so we play 10 versus 10. This is what amazed me. At this level it's amazing. [Declan] obviously had a reaction that his back was to the ball, that they're not in the middle of the park, trying to counter or anything.

"Anyway, I repeat myself; by law if you want to do it you have to do it, but you have to do it in the first half and play 10 against 10. That's it. Very simple."

Brighton took advantage within eight minutes. João Pedro turned home the rebound after David Raya saved Yankuba Minteh's shot, cancelling out Kai Havertz's well-taken 38th-minute opener, lofted over Brighton goalkeeper Bart Verbruggen.

Fuelled by a sense of injustice, Arsenal reorganised and after a short spell in which they seemed flummoxed by how to reorganise with 10 men, Havertz and Bukayo Saka had glorious chances to score, but both were denied by Verbruggen. Brighton inevitably controlled possession and went closest through substitute Yasin Ayari in between those Havertz and Saka chances but had to settle for a point.

"We reacted to what we had to do playing at home with 10 men," Arteta said. "We didn't want to be so deep defending like this, but we read the game and we played the game that we had to play and we should have got rewarded."

There was at least some good news afterwards in that defender Jurriën Timber did not suffer a serious injury and was instead substituted late on with cramp. Timber has been cited as a possible option in midfield given his physicality and quality on the ball. It will likely be something Arteta considers for the challenges ahead, although Jorginho, Thomas Partey and Martin Ødegaard are the most obvious fits to start against Spurs as things stand.

The international break will shape their approach and also give Sterling a chance to sharpen his game ahead of the trip across the capital. Not selected for England by interim coach Lee Carsley, Sterling will instead work at Arsenal's London Colney base and reacquaint himself with Arteta, with whom he developed a strong relationship during three years working together at Manchester City.

"We have to see him, speak to him [about] what he's been doing and how he's feeling about it and try to find quick wins to get him up to speed as quickly as possible and for him to understand what we are looking for from him in the dynamics of the team," Arteta said of Sterling. "We will use that time to do that and get him involved as soon as possible."

And what of coping without Rice or Merino? "This is what happens," Arteta replied. "We have to adapt to that context. That's why we have other players that can fulfill that [role] and [I can] give that opportunity to somebody else."

Perhaps those squad concerns never truly go away.