Chelsea forced Manchester City to place their Premier League title party on hang on Saturday, winning 2-1 to improve their own likelihood of a top-four finish in a dress rehearsal for the Champions League final.
Raheem Sterling gave the home side the lead right before half-time at a clear Etihad Stadium.
Sergio Aguero then missed an attempted Panenka penalty for City before Hakim Ziyech levelled and Marcos Alonso bundled in the winner in the dying seconds.
City could possibly be crowned champions before they play again. Second-placed Manchester United face three matches before Pep Guardiola's men are next doing his thing, against Newcastle on Friday.
The three points lift Chelsea into third spot, six free from fifth-placed West Ham with just three games to go.
Thomas Tuchel's in-form team ended City's dreams of a historic quadruple by beating them in the FA Cup semi-final last month plus they once again proved tricky opponents.
City, who have an enormous 13-point advantage over second-placed Manchester United, are certain to win their third Premier League title in four years but must now await it to be confirmed.
Guardiola made nine changes from the medial side that saw off Paris Saint-Germain in the next leg of the Champions League semi-final in midweek, with Ederson and Ruben Dias the only players to keep their places.
Chelsea made five changes following their triumph over Real Madrid.
The house side dominated possession in the early stages, with Ferran Torres firing over after a thrust down the proper and Benjamin Mendy shooting wide.
Sterling was booked in the 12th minute after catching Timo Werner along with his studs however the punishment could have been worse.
Werner had the ball in the net soon after the half-hour but he was well offside and Sterling had a shot at the other end but clear-cut chances were at reduced.
Ziyech tested Ederson in the City goal as the half-time break neared but occasions later the house side were ahead.
Gabriel Jesus shrugged off Andreas Christensen to break right into the area. He squared, looking for Sergio Aguero. The Argentine's touch was poor but Sterling was on hand to tuck home.
City must have been 2-0 up in first-half stoppage time but Aguero paid the price for attempting a Panenka penalty that was easily saved by Edouard Mendy, drawing the ire of Guardiola.
Jesus won the spot-kick when he was bundled over by Billy Gilmour.
- Chelsea fightback -
As the next half wore on the visitors began to establish a foothold plus they equalised soon after the hour when Rodri lost possession on the halfway line.
Chelsea broke down the proper and Cesar Azpilicueta picked out Ziyech just beyond your area. The Moroccan drilled a minimal shot in to the bottom corner.
Guardiola threw on Ilkay Gundogan and Phil Foden for Torres and Aguero as his side went searching for the win.
Chelsea substitute Callum Hudson-Odoi had the ball in the web with about 10 minutes to go however the goal was eliminated for a marginal offside.
The final was frantic. Sterling had a penalty appeal rejected and Alonso then grabbed a last-gasp winner after an assist from Werner.
Tuchel has transformed Chelsea's fortunes since replacing Frank Lampard at Stamford Bridge in January, losing just two matches on his way to the FA Cup final and Champions League final.
Their remaining three league matches are against Arsenal, Leicester -- their FA Cup final opponents -- and Aston Villa nonetheless they will now be strongly fancied to be eligible for the Champions League for the 3rd season in a row.