Published: 2017-03-19 10:44:47 BdST
Even without the injured Eden Hazard, Antonio Conte's men, who have lost just one game in 2017, triumphed again when Cahill struck three minutes from time to make amends for giving away a first-half penalty.
With only 10 games left, it seems wholly unlikely that the leaders can be caught now and their ecstatic celebrations at the end of a tough game suggested that they believed it may have been the victory that assures their title triumph.
Not that Conte was remotely entertaining any complacency. "We need to take 21 points for the title win. Today was a great win, a good signal, but it is important to continue with the same commitment and work rate as a team," he told the BBC.
Others think the race is already won, though. "It is Chelsea's title now and you could see from their celebrations, we ran them close," said Stoke manager Mark Hughes.
Chelsea had looked set for a comfortable afternoon when Willian scored a 13th-minute free kick, his shot squeezing into the net after a blunder from Stoke keeper Lee Grant, who could only fumble the ball over his own line.
Yet Stoke hit back when Jon Walters, having been fouled by Cahill, picked himself up to score from the penalty spot seven minutes before the break.
Diego Costa became embroiled in running battles with Stoke's defenders, who appeared to try to wind up the volatile striker as he endured a frustrating afternoon chasing his 50th Premier league goal.
He earning himself an early booking and was also involved in incidents which saw yellow cards shown to Bruno Martins Indi and Phil Bardsley.
Chelsea would not be denied and created most of the second-half chances, with Marcos Alonso hitting the bar with a free kick and Pedro being denied by Grant before Cahill swept in the winner.
It ultimately sealed their 19th win in their last 22 league games, with Stoke's misery completed when Bardsley received his marching orders in the dying seconds after receiving a second yellow card for a foul on Cesc Fabregas.