Middlesbrough keeping tabs with Chelsea centre-back Tomas Kalas in this transfer window. Czech defender had a good season in Fulham as he helped the Cottagers to return in Premier League after 4 years. Now he returned to London and search for a new club to change the working place. Blues have too many centre-backs like Rudiger, Cahill, Luiz, Christensen and there is no place for Tomas.

Kalas played un Middlesbrough in the 2015-16 season and the club want to re-sign him with a loan spell. The 25-year-old is contracted with Chelsea until 2021 and his release clause is nearly €5m. Czech international is a high-class defender and can strengthen the club back-line. He joined the London club from Sigma in 2010 with a €6m deal. After that, Tomas was loaned in several clubs and got enough experience to deserve a place in starting line-up

The Boro need to improve the defence and Kalas is the best option in this situation. Sarri probably will permit him to leave Chelsea with a season-long loan and help the Championship club to promote in Premier League one more time. Middlesbrough relegated in Championship in 2017.