Chelsea are reassessing their defensive transfer targets after cooling their interest in Bournemouth centre-back Nathan Ake.

The Blues have been heavily linked with a move to re-sign the 24-year-old after inserting a £40million buy-back clause in the deal which took him to the south coast in 2017.

They also have first refusal on Ake with head coach Frank Lampard in the market for a centre-back this month following the Court of Arbitration for Sport’s decision to reduce their Fifa transfer ban on appeal. Lampard was at Chelsea as a player when Ake came through the ranks following his arrival from Feyenoord as a teenager in 2011 and has had the Dutchman extensively scouted since the season started.

Standard Sport understands those reports have raised concerns about Ake’s suitability for the Blues with Lampard harbouring doubts over whether he is the right fit for the higher defensive line he prefers to play with.

Although Bournemouth beat Chelsea at Stamford Bridge last month, they have lost nine of their last 11 Premier League matches and have slipped into the relegation zone. Ake started six of those matches including Sunday’s 3-0 home defeat to Watford. It remains possible Chelsea could yet pursue a deal for Ake given the simplicity of doing so in a typically fraught January market but the fact they are actively exploring other options is further evidence of their uncertainty over his ability.

Chelsea were quoted an asking price of £50m by Brighton for England international Lewis Dunk, who is keen on a move to west London, while they also have an eye on West Ham’s Issa Diop.

Lampard allowed David Luiz to leave for Arsenal prior to the start of the season but last week ruled out Andreas Christensen departing this month despite interest from AC Milan.

It appears he is willing to give the 23-year-old a chance to prove himself during the second half of the campaign in competition with Fikayo Tomori — who has exceeded expectations in a breakthrough campaign — and Antonio Rudiger after he finally overcame persistent injury setbacks a month ago to feature regularly.

Kurt Zouma is also hoping for a prolonged Chelsea career given he has a contract until 2023 and has made 29 appearances in all competitions under Lampard this term.

Chelsea are keen to strengthen at the back, however, with other candidates under consideration including Albanian teenager Marash Kumbulla.

The 19-year-old, who plays for Hellas Verona in Italy, is attracting interest from several European clubs and is thought to be available for less than £20m, although a potential bidding war could drive that price up.

Should no centre-back deal prove suitable, Lampard could decide to wait until the summer given the Blues are presently in the top four.