Gabriel Jesus scored the only goal as Manchester City beat Chelsea 1-0 at Stamford Bridge to move level on points with their Premier League title rivals.
City lost three times to Chelsea in the space of six weeks at the end of last season, including in the Champions League final, but Pep Guardiola finally got the better of Thomas Tuchel in Saturday's contest.
After dominating the first half without managing to test returning Chelsea goalkeeper Edouard Mendy, the visitors opened the scoring eight minutes after the restart through a heavily deflected Jesus shot.
That sparked the game into life as City missed two big chances and Romelu Lukaku had a goal ruled out, though Jesus' strike proved to be the difference as top-flight champions City inflicted a first defeat of the season on European champions Chelsea.
Tuchel shifted from his usual 3-4-3 to a 3-5-2 to accommodate Timo Werner and Lukaku up top for the first time and Chelsea struggled to get going.
All City had to show for their dominance of possession in a quiet first half, though, was a sliced Jesus shot at the back post after being found by Phil Foden.
Guardiola's side picked up from where they left off in the second half and opened the scoring with the game's first attempt on target.
Joao Cancelo's long-range effort hit Jesus and the Brazil striker took over with a shot on the turn that flicked off Jorginho on its way past a wrong-footed Mendy.
Mendy pulled off a fine low save to help Jack Grealish's shot past the post and substitute Thiago Silva blocked Jesus' drive on the line as City pressed for a second.
Those missed chances almost came back to haunt City when Lukaku tapped the ball into the net at the other end, but Kai Havertz was offside in the build-up and it was ruled out.
Chelsea desperately went in search of a leveller, yet the best of the remaining opportunities fell to City's Grealish, the midfielder again denied by Mendy when through on goal.