Sheffield United: Blades will get tough over transfer fee if they decide to firm-up their interest in striker

Although arranging talks with Neal Maupay and Oli McBurnie is Chris Wilder's immediate priority, The Star understands Assombalonga's name also featured on the final list of potential acquisitions he presented to Bramall Lane's hierarchy this week.

But sources close to United last night confirmed that a number of factors, including the EFL's Profit and Sustainability regulations, mean they now value the 26-year-old at significantly less than the £15m Middlesbrough paid to sign him in 2017.

Despite scoring 31 goals in only 65 starts since moving to Teesside, Assombalonga faces an uncertain future in the North-East as chairman Steve Gibson investigates ways of streamlining how his club goes about its business. With Tony Pulis departing after failing to reach the Championship play-offs last term, the former Stoke manager's successor could choose to sacrifice Assombalonga in order to re-profile Middlesbrough's squad.

McBurnie, the Swansea City striker, and Brentford's attacking midfielder Maupay have both attracted interest from United since their promotion to the Premier League was confirmed.

Ollie Watkins, Maupay's team mate at Griffin Park, has also been linked with United as Wilder looks to increase the firepower at his disposal. Aged 23, Watkins joined Brentford from Exeter City two years ago.

Brighton and Hove Albion are also thought to be monitoring McBurnie's situation at the Liberty Stadium while Aston Villa could resurrect a bid for Maupay after failing to prise him away from Griffin Park in January.

But United's refusal to explore alternative options suggests they believe the two men remain viable targets. Indeed, given the wealth of their new owners, Villa could choose to pursue established top-flight names after winning the Championship play-off final.