Premier League champions Chelsea have signed teenage defender Tomas Kalas from Czech Republic side Sigma Olomouc. The 17-year-old defender will not be joining the club for a further year as he will return to the Andruv Stadium in Olomouc on a year-long loan deal. The youngster has been a target for many top European clubs, but Carlo Ancelotti's Stamford Bridge club moved quickly to land the talented Czech star. Financial details of the deal have not been disclosed, although reports claim that Olomouc could earn in the region of £5million from the sale of the player. Chelsea Academy boss Neil Bath said: "Tomas has signed, but will spend the first year on loan at his club, Sigma Olomouc, in the Czech Republic. "He is now going into the Under 18s, and made his first-team debut last season. Very athletic and quick, he is a very good one-on-one defender and comfortable on the ball. "We feel there is a lot of potential in the player, and we feel at the minute it is the right time to get him, but it would be good for him to stay there and get first-team experience, and we look forward to him joining us next year. "Obviously we will stay in touch and he will come across here when appropriate. He is a right-sided centre-half who can play right-back.