Chelsea defender Tomas Kalas has signed a new four-year deal with the Premier League club and rejoined Championship side Fulham on a season-long loan deal.
Kalas made 40 appearances on loan at Craven Cottage last season.
The 24-year-old, capped seven times by the Czech Republic, has featured only four times for Chelsea since signing from Sigma Olomouc in July 2010.
"We appreciate Tomas so much after the way that he battled for us last season," said vice chairman Tony Khan.
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