Manchester City took revenge for their Champions League final loss to Chelsea and secured a big three points in the early running for the Premier League title with a 1-0 win at Stamford Bridge.
Gabriel Jesus' deflected effort eight minutes into the second-half separated the sides, but City should have been more convincing winners as they laid down a marker after losing to Chelsea three times towards the end of last season.
The most painful of those came in Porto as Chelsea lifted the Champions League to deny City the crowning glory of the club's rise since an Abu Dhabi takeover in 2008.
Pep Guardiola was fiercely criticised for his decision to start without a natural holding midfielder when the sides last met in May.
That error was rectified with the return of Rodri and the Spaniard's poise helped Guardiola's men completely dominate possesion.
However, City's lack of a prolific goalscorer to turn that dominance into goals was again exposed.
Guardiola bemoaned on Friday that his side lack a "weapon" of the likes of Chelsea's record signing Romelu Lukaku or Manchester United's Cristiano Ronaldo to decide games inside the box.
Instead, City have to rely on the collective of a richly assembled squad of creative midfielders as Guardiola named Kevin De Bruyne, Phil Foden, Jack Grealish and Bernardo Silva in his starting line-up.
For all of City's patient probing, it was when they took a pot shot from long-range that they looked most likely to break the deadlock before the break.
Rodri's piledriver would have tested Edouard Mendy but for a deflection that took it over before De Bruyne also fired over when the Belgian found a rare pocket of space.
Rather than stepping into the shoes of the departed Sergio Aguero, Jesus has found himself deployed as a right winger so far this season.
The Brazilian should have done better with City's best chance of the first-half when he sliced well wide after controlling Silva's cross to the far post.
However, Jesus got the break City's performance deserved to open the scoring on 53 minutes as his effort deflected off Jorginho to leave Mendy flat-footed.
That was just the 15th Premier League goal Chelsea had conceded in 25 games since Tuchel took charge.
But there could have been plenty more but for a combination of wasteful finishing and some brilliant last-ditch defending.
City's £100 million summer splash on Grealish rather than a goalscorer has been questioned, but the England international came to life after the break and only a stunning save by Mendy low to his left prevented the visitors quickly doubling their lead.
Jesus' lack of a killer instinct was again exposed when he appeared to have an open goal after another dangerous Grealish burst, but his low finish allowed international teammate Thiago Silva to clear off the line.
Tuchel's response was to send on Kai Havertz, the hero of Porto with the only goal, but the German was well offside when he teed up Lukaku for a tap in.
Chances continued to come and go the other end as Grealish was denied again by Mendy when clean through.
But the Premier League champions' profligacy was not punished and United's shock 1-0 home defeat to Aston Villa capped a stunning Saturday for City.
Guardiola's side move level on 13 points with Chelsea, United and leaders Liverpool, who face Brentford later.