Arsenal 2, Brighton and Hove Albion 0
Arsenal manager Arsene Wenger relished proving his critics wrong as he celebrated his 21st anniversary in the job with victory over Premier League newcomers Brighton.
Goals from defender Nacho Monreal and midfielder Alex Iwobi earned the Gunners a third win in seven days and continued their flawless home record this season.
Wenger's men have now taken six wins and a draw from their seven games since a 4-0 thrashing at Liverpool just over a month ago, to the satisfaction of their long-serving boss.
"I knew that after the game in Liverpool everybody did write us off and it would just depend on how much we respond," said the Frenchman, whose team climbed to fifth.
"Nothing is permanent. You aren't bad in a permanent way if you can do something about it, and you are not good in a permanent way if you don't keep your urgency. We responded in a united way and we put some wins together and some good performances as well."
Wenger, who insisted it was too early in the season to say whether Arsenal could catch the frontrunning Manchester clubs, claimed he had not know about his work anniversary until prompted today.
"I wouldn't like too much to reflect on that," added the 67-year-old, who almost left the club in the summer. "I kept my focus on my job always. When you are 21 years you know that you have good and bad moments. Nobody can make 21 years and only fly. What I love in the game is as well to deal with bad moments and to find the response."
Arsenal's £46.5m record signing Alexandre Lacazette had scored four goals in his first five Premier League starts and he almost continued that streak just 60 seconds in when he hit the post from the edge of the penalty box.
The hosts would not be denied for long, however, though the 16th-minute breakthrough came from the less likely figure of Monreal, who fired into a partially unguarded net after the Seagulls had only half-cleared Granit Xhaka's free-kick.
Brighton, making a maiden trip to Emirates Stadium and their first away day at the Gunners since 1983, almost equalised moments later when midfielder Solly March thudded an upright from 20 yards. Defender Lewis Dunk could not adjust his feet in time to divert the rebound on target.
Visiting goalkeeper Mat Ryan made two smart stops to deny Lacazette, after he pounced on Dunk's poor control, and Aaron Ramsey, following an end-to-end counter-attack, as Arsenal hunted a second goal before half-time.
Iwobi delivered 10 minutes into the second half, lashing his first Gunners goal since January high past Ryan from close range after Alexis Sanchez's backheel befuddled Brighton's defence.
Dunk did more than anyone to prevent Arsenal scoring again. He cleared off the line when Sanchez's shot beat Ryan and then, after March had also denied Sead Kolasinac from under the crossbar, made a last-ditch block on Lacazette.
Wenger's men, perhaps jaded from a week in which they had already seen off West Brom and BATE Borisov in Belarus, tailed off alarmingly in the last 20 minutes and Brighton almost took advantage. Substitute Glenn Murray beat Shkodran Mustafi to a Pascal Gross cross but his header flashed just wide of the near post.
Chris Hughton's side lie 14th after seven games. "I don't think you're ever satisfied -there were certainly a couple of games where we could have got more - but we're a new team in this division and learning. We've played Arsenal and Man City and we've not been out of sight. We could have done more, but ok."