Goals from Kevin De Bruyne, a brace from Sergio Aguero and a late fourth from Bernardo secured victory in a game where the visitors played their full part.
The win came at a cost, however, with the champions losing Aymeric Laporte in the first half to what looked like a painful knee injury.
READ: Laporte update
City wasted no time taking command against the Seagulls.
The last home game against Spurs saw just two goals converted from 30 shots – this game saw the Blues take the lead with the first shot of the game and just 68 seconds on the clock.
David Silva, inevitably, was the creator, as he darted in behind the Brighton defence before picking out De Bruyne with a low cross and the Belgian made no mistake from eight yards.
Aguero and De Bruyne would both see shots fizz inches wide before 20 minutes had been played, but the visitors’ clever tactics with and without the ball made for a lively contest.
Fast and direct with in possession, the pattern was reversed without the ball to a compact unit attempting to crowd out City’s creativity around the box.
Silva missed a sitter on 30 minutes after good work by Raheem Sterling as the Blues looked to give themselves breathing space but the Spaniard, for once, got his angle wrong as he skewed a shot past the post from a couple of yards out.
Not long after, Aymeric Laporte was stretchered off with what looked like a knee injury following a clash with Adam Webster and was replaced by Fernandinho.
City responded well to the blow and two minutes before the break, the lead was doubled.
The impressive Riyad Mahrez played a clever back-heel to De Bruyne who moved into the box, found Aguero and after working himself a couple of yards of space, the Argentine thumped home his fourth of the season.
Brighton continued to threaten after the restart and should have halved the deficit on 50 minutes when Oleksandr Zinchenko was dispossessed on the left and the ball eventually found its way to Leandro Trossard who should have scored, but Fernandinho headed his shot wide from point blank range.
If it was a shot across the bows, it was heeded within minutes as Silva combined with Aguero superbly and ended with the City striker curling a beauty past Matt Ryan and into the top right-hand corner for his second of the game and City's third.
And the Blues' talisman striker set up the fourth of the afternoon, slipping in Bernardo to score just seconds after coming on for the skipper.
It felt a little harsh on Brighton who will trouble a lot of teams this season and will travel home ruing missed chances at crucial times.
Fernandinho: Impeccable cameo
After replacing Laporte just before the break, Fernandinho effortlessly slipped into action in this, his first game of the season.
Crucial tackles and a wonderful headed clearance were just a couple of highlights from our classy Brazilian.
Pep will be delighted to have him back.
What it means…
City returned to the top of the Premier League table ahead of Liverpool's game at Burnley.
The champions will stay in pole position if the Merseysiders draw or lose at Turf Moor.
Star man: Kun Aguero
There were terrific performances from Mahrez, Silva and Rodri - plus a terrific cameo from Fernandinho - but Aguero's clinical strikes were the difference on the day. - not to mention an assist for Bernardo!
There is a two-week break before the Premier League resumes with a trip to Norwich City.
Then, the genteel pace of games that had prevailed in the first month of the campaign shifts up a couple of gears!