Chelsea are chasing Ajax centre back Jan Vertonghen for the January market.

The Daily Mail says Chelsea scouts have watched the Belgium star several times this season, including in last week's Champions League defeat by Real Madrid in Amsterdam.

Bolton defender Gary Cahill remains manager Andre Villas-Boas's first-choice central defender, given his Premier League experience.

However, Chelsea representatives have been impressed with Vertonghen and the 24-year-old is viewed as an option if a move for Cahill fails.