Swansea City face a battle to hold on to Alfie Mawson in the January transfer window amid serious interest from West Ham United, who are expected to make a bid for the central defender. The Hammers have identified Mawson, who caught the eye for England Under-21s at the European Championship finals in the summer, as one of their key targets next month and are ready to test Swansea’s resolve. The Welsh club, who are bottom of the Premier League and without a manager after Paul Clement’s dismissal on Wednesday, rate Mawson highly and are determined to hold on to him as they try to plot a route to survival. They opened new contract talks with Mawson some time back – he has two and a half years remaining on his current deal – and those discussions remain ongoing, with Swansea hopeful that an agreement can be reached. Although the defender is settled at Swansea, the club’s league position makes them vulnerable to bids from West Ham and other potential buyers. West Ham would be expected to offer around £20m for Mawson, which is likely to fall well short of Swansea’s valuation, especially as the club cannot afford to lose another of their more influential players after the damaging departures of Gylfi Sigurdsson and Fernando Llorente in the summer. Signed from Barnsley for £5m in August last year, Mawson, now 23, had to be patient to get his chance at Swansea but impressed after Clement took over in January. He scored four goals during the second half of the season and formed an excellent partnership with Federico Fernández at the heart of the Swansea defence, helping the club to stave off the threat of relegation and earning him an England Under-21 call up.