The Spanish striker was one of the Blues’ key players in Antonio Conte’s first campaign in charge at the west London club as he helped to inspire the Blues to the Premier League title in the 2016-17 campaign.
However, Costa reportedly fell out with Conte mid-way through the season and he was eventually sold back to Atletico Madrid last summer after being deemed to be surplus to requirements at Stamford Bridge.
Nevertheless, Costa played an influential role at Chelsea FC during his time with the west London club, and Fabregas believes that he greatly improved some key aspects of his game with the Blues.
Speaking to the Daily Telegraph, Fabregas said: “At Chelsea, in the last few years he improved a lot his first touch and his combination play.
“efore he was more of a runner, he didn’t like the ball to his feet too much but he improved a lot and I believe now he is ready to play in any type of style.
“He is also good for the squad off the pitch. Maybe with Spain he is a little bit more reserved than he was at Chelsea, but he is the way he is. He is always a positive influence.”
Costa scored twice for Spain in their thrilling 3-3 draw with Portugal at the World Cup on Friday night.
The Spanish forward will be hoping to help fire his national side to glory, with Fabregas having missed out on a call-up to the World Cup following Chelsea FC’s mixed campaign last term.
The Blues finished fifth in the Premier League and won the FA Cup trophy last season under Conte.
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