That is according to player-turned-pundit Mark Lawrenson.
Antonio Conte endured a difficult start to life in charge of the Blues.
In September, Chelsea followed up their 2-1 defeat at home to Liverpool with a capitulation in north London.
But that victory for Arsenal did kick-start the Blues’ season as they went on a 13-game winning run in the Premier League.
Chelsea boss Antonio Conte endured a torrid visit to the Emirates in September as Arsenal won 3-0
The Gunners now sit nine points behind Chelsea in the title race, and a loss at Stamford Bridge will all but end Arsenal’s challenge for top spot.
The reverse result will be in Conte’s mind though too, and Lawrenson feels the Blues’ change since to a 3-4-3 set-up will show the difference tomorrow (12.30pm).
“Chelsea just keep rolling along at the top of the table,” Lawrenson wrote in his BBC Sport column.
“They have had a good week because they have extended their lead at the top of the table despite being held at Liverpool, because they would have expected Arsenal and Tottenham to have both won their midweek games.
Antonio Conte's Chelsea have improved dramatically since their defeat at Arsenal
David Luiz's outrageous celebration after cheeky free-kick against Liverpool
Wed, February 1, 2017
David Luiz let it all out after scoring a belting free-kick for Chelsea in their 1-1 draw against Liverpool at Anfield
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David Luiz sparked wild celebrations with his goal against Liverpool last night
This is a very different Chelsea side now, not just in formation
“There is a part of me which thinks Arsenal could go there and be brilliant but, even if they are, Chelsea will be hard to break down.
“I also think Antonio Conte's side will be thinking they have something to prove against Arsenal after losing heavily at the Emirates Stadium in September.
“This is a very different Chelsea side now, not just in formation since their switch to three at the back later that month, but also in mentality – the title is in their sights now.”
As Chelsea’s showdown with Arsenal is the early kick-off this weekend, a win will see them extend their lead at the top to 12 points at least temporarily.