The Croatian maestro was missing during his country’s visit to Wembley on Sunday
Chelsea could be without midfield star Mateo Kovacic when they face Tottenham on Saturday.
The Croatian is a major doubt for the game after picking up a muscular injury during the international break.
Kovacic played no part in his country’s 2-1 defeat to England at Wembley on Sunday and ESPN reporter Liam Twoney revealed he did not train the previous day.
However, there is hope the Real Madrid loanee will recover in time for the London derby.
When asked how the the injury is after the game, Kovacic replied: “Good, better.”
Chelsea are not short of options in midfield, with Ross Barkley and Ruben Loftus-Cheek ready to fill in should Kovacic be unavailable.
Barkley has staked his claim for a starting position ahead of Kovacic with three goals and three assists in the Premier League this season, while Loftus-Cheek bagged a hat-trick in the Europa League against BATE Borisov.
The Blues signed Kovacic on a season-loan from the Bernabeu during the summer, as part of a move which saw Thibaut Courtois go to Madrid.
While he is yet to open his Chelsea account, the midfielder has been an integral part of Maurizio Sarri’s incredible unbeaten run in all competitions.
The west London side are the only team in Europe who remain undefeated this season, although they are four points behind leaders Manchester City in the Premier League.