The Spanish playmaker was a dominant force in midfield as he helped the Blues secure a 1-0 victory over his former club at Emirates Stadium.
Fabregas has come in for plenty of criticism this season for a string of below-par displays for the west London side.
However, the 28-year-old Spain international seemed to be approaching his best form again if his display against Arsenal was anything to go by.
And the former Barcelona star has been working hard in the gym this week as he bids to help Chelsea reach the fifth round of the FA Cup.
Fabregas gave a glimpse into his workout on Monday morning as he posted the picture above on his official Snapchat account.
Fabregas has made three assists and scored one goal in 22 Premier League games so far this season.
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