The Blues took a first-half lead thanks to Oscar’s second strike of the week after the Brazilian netted against Bolton Wanderers in midweek.
Diego Costa then scored his eighth Premier League goal of the season in the 58th minute in west London.
And Willian sealed maximum points for the home side with his first strike of the season in the 79th minute to keep the Blues three points clear of Southampton.
Summer signing Fabregas, 27, posted the picture above on Instagram after the game and wrote: “Very good performance today.
“Big game on Tuesday, let’s keep it going.”
Chelsea and Arsenal are the only two remaining unbeaten teams in the Premier League this season.
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