The Blues head into the game looking to return to winning ways after they were held to a 1-1 draw by Liverpool at Anfield in midweek.
Arsenal are also looking to bounce back after their shock 2-1 loss to Watford at The Emirates on Tuesday night.
Costa will be expecting to line up against the Gunners as Antonio Conte’s men look to gain revenge for their 3-0 loss to Arsenal at The Emirates back in September.
And he certainly looked like he was being put through his paces by Terry at Cobham on Friday as the Blues completed their final training session ahead of Saturday’s showdown.
Terry shared the photo above on his personal Instagram account and wrote the caption: “Training today ⚽️ @chelseafc @diego.costa @chalobah”
Chelsea are currently nine points clear at the top of the table, while Arsenal are third in the top flight.
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