Earlier, Cahill had been penalised for a foul on Jonathan Walters, which allowed the Stoke man to cancel out Willian's opening goal.
Erik Pieters conceded a needless corner with a poor back-pass to Grant and the Dutchman's clearance from Luiz's header came to Cahill to fire home.
Cahill was to make up for giving away the penalty however as he smashed home a corner to steal the three points with five minutes left.
Chelsea travel to Stoke City on Saturday (18 March) looking to continue their unbeaten run in the Premier League and put more distance between them and the chasing pack at the top of the table.
"Diego is showing in all this season, not just this game, great discipline, great commitment".
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A good thing , too, because a weaker spirit would collapse at the rom-com complication Tara encounters in the pre-credits opener. Danny is fighting to get control of the company his father left behind, as his parents actually did die in that crash.
Surprisingly it took Costa 17 minutes to take the bait and earn the game's first booking for dissent.
Conte was without Hazard for the clash but he made to forget his worries as Willian scored a wonderful free-kick from an acute angle to give Chelsea the lead. In fact he's never been shown a red card in his nearly three seasons in the Premier League, despite his confrontational style of play, showing he knows exactly what he's doing.
13' - GOAL! Stoke 0-1 Chelsea (Willian).
Gary Cahill celebrates scoring the victor for Chelsea at Stoke.
Clearly concerned with Stoke's aerial threat, Conte favoured Matic over Fabregas this time and Chelsea missed the latter's poise as well as his vision in the opening minutes, with passes going astray and spells of possession more mechanical and less imaginative than usual.
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He added the relationship is crucial not just for China and the U.S. , but also for regional and global peace, security and stability.
Pedro blazed over a good chance to restore the visitors' lead before Bardsley clattered into Costa to be booked in the final stages of a tempestuous half.
Asked whether it was Chelsea's title to lose, he added: "To have a 10 points gap, 13 at the moment, but I like to think our opponents will win tomorrow".
Chelsea is now at the top of the Premier League and will face Stoke City today at 8:30 PM.
"I played in that position for many years and I think he's an outstanding striker, but on occasions he's got elements of his play that he doesn't need to have".
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Attorneys general from Massachusetts , Oregon , New York , Minnesota , and California have all signed on to Ferguson's suit. Trump said that if they had announced the previous ban with more than a week's notice "bad" people would rush into America.