Chelsea have “asked to be kept informed” as the battle to sign Arminia Bielefeld defender Amos Pieper heats up, according to The Mirror.

The English tabloid claim that the “in demand” centre-half is not only being targeted by the Blues, with Newcastle, Southampton and Borussia Dortmund also keen on the player.

Pieper’s contract at Bielefeld expires in June so he will be available on a free transfer. Despite playing for a struggling a side, his performances have impressed scouts.

Bielefeld were promoted to the German top-flight a couple of years ago. They stayed up last season on 35 points, even though the Bundesliga outfit conceded 52 goals, but they are in danger of being relegated this campaign, currently sitting second from bottom with three games left.

Pieper is still only 24 years of age, and he could well be seen as a useful squad player by manager Thomas Tuchel, who is also believed to be targeting more high-profile centre-backs, including Sevilla’s Jules Kounde and RB Leipzig’s Josko Gvardiol.