Chelsea midfielder Mateo Kovacic is in talks over a potential move to Zenit St Petersburg.

The 24-year-old Croatia international is on loan from Real Madrid for the season but there is no option to buy in his contract and his representatives are working on his next move after holding talks this week.

Chelsea coach Maurizio Sarri said last month that he wished to make Kovacic's loan permanent. However, Sarri's own position is in doubt and Chelsea will only be able to acquire Kovacic if their appeal to FIFA against a two-window transfer ban, which was heard last Thursday, results in the punishment being overturned or delayed.

Croatia international Mateo Kovacic is in talks with Russian side Zenit St Petersburg

The Chelsea midfielder would link up with another former Blues player Branislav Ivanovic

Chelsea manager Maurizio Sarri is determined to keep Kovacic but his own future is uncertain

'I want to try with Kovacic,' said Sarri. 'He is only on loan, of course, but I'd like very much that Kovacic will stay with us.

'You know very well that, in that position, we have some problems because we have only Jorginho. In my opinion, Kovacic could become a very good central midfielder.'

It's understood Zinedine Zidane is happy to allow Real Madrid to seek a permanent sale as he looks to use funds to overhaul his tired squad with Chelsea's Eden Hazard top of his wishlist.

Kovacic has made 43 appearances and is favoured by Sarri but has failed to convince many at Stamford Bridge. He has started regularly in the Europa League and often alternated with Ross Barkley in midfield.

Zenit are top of the Russian League and have former Chelsea defender Branislav Ivanovic among their ranks.