According to the Daily Telegraph, Courtois and Costa will each sign a new deal after being convinced by new manager Antonio Conte that they will be happy staying at Chelsea.
Both players arrived at Chelsea in the summer of 2014 after helping Atletico Madrid to La Liga glory the previous season (Courtois had been on loan in Madrid for three years), but both were linked with returns to Spain after dismal individual campaigns in 2015/16.
Neither player was able to reproduce the form that saw Chelsea cruise to the Premier League title in 2014/15 and it was difficult to imagine how they might possibly recover while still in west London.
Yet Conte's impact has been huge. The Italian has the squad playing as a unit once more and has now already masterminded a rise back to the very top of the table for the first time since the club was being presented with the Premier League trophy in May 2015.
As a result of the complete turnaround, Courtois and Costa are ready to commit. Their current contracts are not due to expire until June 2019, but talks over extensions that will take each player into the next decade appear set to begin in the new year.
Each player could see up to a £50,000 rise to their weekly pay packets, with Costa tipped to earn close to £200,000-per-week and Courtois expected to be given a contract worth around £150,000 each week.
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