Eden Hazard raised his game to the standard of Diego Costa as Chelsea ran out impressive 3-0 winners against Leicester City at Stamford Bridge.
Costa opened the scoring with his seventh goal of the season after a Nemanja Matic flick-on from a Hazard corner found him unmarked at the back post. Hazard scored the second goal after a Matic through-ball found him, via a flick from Pedro, with the Belgian rounding Kasper Schmeichel before slotting home.
Victor Moses killed the game off in the second half after Chelsea were able to bring on three academy players as substitutes, including Nathaniel Chalobah, who provided a stunning assist for the final goal of the match.
The reason for the complete and utter dominance was the combination play between Hazard and Costa, who sent a warning to their former manager Jose Mourinho that they are hitting their best form as Manchester United await a trip to west London next week.
Meanwhile, Leicester failed to have a single shot on target until late in the second half, when they were already 2-0 down, as Antonio Conte's men begin to look really comfortable in the newly-applied 3-4-3 formation.
N'Golo Kante was roundly booed by the away fans, but put in arguably the best performance of his Chelsea career to date, offering a threat going forward while being super effective at winning the ball back against his old team-mates.
Hazard's form will worry Manchester United the most, as the former PFA Player of the Year got back to the level he showed in his first three games of the season after a temporary decline in his last four appearances for the Blues.
Costa's goals have become a guarantee with five in his last five games, but he was carrying the huge weight and pressure of Chelsea on his own shoulders during the bad run as he was one of the few players to display any kind of consistency.
Hazard could be ready to join him and show a consistent level in the new system that allows the wing-backs to take the responsibility for tracking back while he is able to focus on what he does best, which is twist, turn and provide his match winning moments.
Kante and Matic also provide the protection to allow the Blues's front three to focus on their interplay to be truly creative, and to do it against the team who took their title last season.
Manchester United will have to come up with something special to win at Stamford Bridge next week, with Chelsea looking devastating, despite having the likes of Willian, Cesc Fabregas and Oscar out of contention for this match.
Conte will be hoping that his tactical masterstroke will allow Hazard to reach the highs that Costa has shown and, if the pair can keep working together like they did against Leicester, then they will worry the best teams in the Premier League once again.