Phil Foden's first half strike was enough for Manchester City, who edged past a spirited Brighton side at the Etihad Stadium.
City dominated the proceedings in the first 45, though it was Brighton who came out fighting in the second half, but they failed to test Ederson between the City sticks.
Raheem Sterling spurned the chance to wrap up the three points from the spot as he blazed his penalty over the bar, but it mattered not as the hosts hung on for all three points.
Story of the Match
Manchester City came into the game on a 13-match unbeaten streak in all competitions, with the Citizens unbeaten in their last seven in the Premier League.
They faced a Brighton side without a win in their last eight Premier League outings, although they did book their place in the fourth round of the FA Cup last time out as they edged past League Two Newport County on penalties.
Pep made four changes to his starting XI from the cup win over Birmingham, with Ederson, John Stones, Oleksandr Zinchenko and Ilkay Gundogan brought back into the fold.
Meanwhile there was a first Premier League start for Brighton forward Percy Tau, after the summer signing impressed during his Seagulls debut at Rodney Parade on Sunday.
Neither side took full control of the game in the early stages, with the first real chance falling to the feet of Manchester City captain Kevin De Bruyne after 15 minutes.
Some fine footwork by the inform Ilkay Gundogan helped the German to create the space to slip the ball in to the Belgian, however his shot from a tight angle was saved comfortably by Robert Sanchez.
Brighton were without a number of key men in the forward roles - including Adam Lallana and Danny Welbeck - but they still found ways to cause City trouble, with Leandro Trossard going close after 18 minutes.
The Belgian winger was played in down the left and found himself one-on-one with John Stones, cutting inside and curling a right footed effort narrowly wide.
Manchester City were the victims of a pass back during their last Premier League outing against Chelsea, but they were the beneficiaries of one this evening as Sanchez picked up what the referee adjudged to be a pass by Adam Webster.
The indirect free kick, some 12 yards out, was touched back by Bernardo Silva towards De Bruyne, but his effort was blocked behind by Alexis Mac Allister.
Graham Potter would've targeted set pieces as a route towards goal for the visitors tonight, but it was Manchester City who almost opened the scoring on the back of the Seagulls first corner of the evening.
Ederson's quick distribution sent De Bruyne away, with the Belgian finding the run of Foden down the right before collecting the ball back himself and forcing Sanchez into a fine save low to his left.
Brighton defended astutely during the first 45 and it looked like they would head into the sheds level, but Phil Foden had other ideas.
The goal began with a fine challenge by Ruben Dias on the halfway line, with Gundogan collecting possession and finding De Bruyne on the charge.
KDB exchanged a couple of passes before finding Foden on the run inside, with the English youngster firing in what is become a trademark low drive from the edge of the box, beating the outstretched reach of Sanchez to give the hosts the lead at the break.
Brighton registered their first shot on target early in the second half as Davy Propper's strike from the edge of the box was easily dealt with by Ederson.
Then came a host of Manchester City chances.
The first fell to the feet of Riyad Mahrez, with the Algerian curing an effort wide having been put through one-on-one. Replay's showing that Mahrez was marginally offside anyway.
Then came two chances in quick succession, as Gundogan saw his strike saved, with the rebound falling the way of Bernardo Silva, who struck his effort off the crossbar.
Brighton's counter attacking game was causing City problems though, and they soon found themselves inches away from equalising as Bernardo whipped in an inch perfect ball from the left that marginally evaded the outstretched leg of Propper at the back post.
Many had expected Brighton to struggle, especially given their gruelling contest at Newport last time out, but it was the visitors who looked the more likely as the second half progressed.
The introduction of Solly March and Neal Maupay gave Potter's men the extra impetus up top, but for all of their hard work, they struggled to create anything to test the returning Ederson.
City once again found themselves grateful for the resurrection of John Stones, with the Englishman on hand to prevent Neal Maupay from getting in behind as Brighton continued to push for what looked the most unlikely of equalisers when the halftime whistle blew.
Manchester City were handed the opportunity to wrap up the three points from the spot in injury time as De Bruyne was brought down by the Brighton keeper.
Somewhat surprisingly it was second half substitute Sterling who stepped up to take it, however it seems unlikely he'll take another as he blazed the penalty over the bar, his third consecutive PL penalty miss.
Brighton sent 'keeper Sanchez up for a late free kick as Potter threw his Hail Mary in hope of a late equaliser, but it wasn't to be as Pep and his side hung on for what could prove to be a huge three points in the title race.
Manchester City: Ederson; Zinchenko, Stones, Dias, Cancelo; Rodri, Gundogan, Bernardo; Foden (Sterling '81), De Bruyne (C), Mahrez (Jesus '66).
Brighton & Hove Albion: Sanchez; Bernardo, Webster, Dunk (C), Burn, Veltmann; White, Tau (Maupay '67) Propper (March '67); Trossard, Mac Allister