Middlesbrough loanee would consider permanent switch from Chelsea
The 23-year-old Czech Republic international has spent the last 16 months on loan at Aitor Karanka's side from Chelsea, where he signed a new three-year deal last summer.
But the defender has made only two starts for the Blues since arriving at Stamford Bridge in January 2011, compared with the 47 appearances he has made for Middlesbrough.
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Hide AdKalas said: "I don't know how many games I've played since I came - probably around 40, which is not bad in one and a half years.
"That's why I came here, to play games and hopefully I'll keep playing next season - maybe here.
"If I could get the deal [to move to Middlesbrough permanently], I would really think about it. Yes, why not?"
Head coach Aitor Karanka and chairman Steve Gibson are already planning for life in the top flight following a seven-year absence after the club finally secured its return by finishing as runners-up to Sky Bet Championship winners Burnley.