Chelsea defender Kalas set for Middlesbrough loan

The centre-back will join Blues duo Jamal Blackman and Patrick Bamford, who has extended his stay at the Riverside, while Aitor Karanka also maintains an interest in Lewis Baker

Chelsea have agreed a deal with Middlesbrough to send defender Tomas Kalas on loan to the Riverside.

Boro have moved for the 21-year-old after Chelsea recalled the Czech defender from a spell with Bundesliga side Koln, where he started just two games.

The promotion-chasing Championship side need cover in defence, with Damia Abella and Ryan Fredericks out injured and Emilo Insue set to captain Equatorial Guinea at the Africa Cup of Nations.

Kalas's move to the Riverside should be concluded in the next 48 hours and he could link up with his new team-mates by Monday.

Kalas's loan is the fourth deal concluded between Chelsea and Middlesbrough this season following moves for Patrick Bamford, Kenneth Omeruo and Jamal Blackman.

Bamford recently extended his stay with the Championship club after an impressive start to the season with Boro, with Chelsea understood to have rejected offers from other clubs for the forward.

Goal understands Sunderland tried land to the 21-year-old, but Jose Mourinho insisted that he remain with his former Real Madrid assistant Aitor Karanka, now head coah at the Riverside.

Karanka is also understood to maintain an interest in 19-year-old Blues midfielder Lewis Baker.