Middlesbrough loan Kalas

Championship side Middlesbrough have signed Chelsea defender Tomas Kalas on loan.

Kalas spent the first half of the season on loan at Bundesliga outfit Cologne, but failed to make a single senior appearance.

The centre-back, who can also operate on the right side of the defence, will hope for regular first-team football with a Middlesbrough side pushing for a return to the Premier League.

Since joining from Sigma Olomouc, Kalas has made only two appearances for Chelsea, which came against Liverpool and Cardiff City last season.

But the 21-year-old does have a senior international cap, featuring in the Czech Republic's 3-0 friendly win over Slovakia in November 2012.

Kalas is available for selection for Middlesbrough's visit to Reading on Saturday.