Apparently the Hammers have already held talks with United over the potential transfer of Fleck.
Yet with three-and-a-half years left on his contract at Bramall Lane, surely the Blades will demand more for the Scot?
Fleck is also enjoying the best form of his career under manager Chris Wilder. The 27-year-old was named the club’s player of the year in 2017/18 upon their return to the Championship.
This season Fleck has once again been instrumental in helping United to their current position of third in the table. The midfield ace has played 27 of their 29 league matches so far in 2018/19.
At 27, Fleck is also in the prime of his career.
How much should Fleck cost?
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Looking at this campaign alone should suggest that the amount paid for a quality Championship midfielder is higher than £4m.
Middlesbrough completed the signing of George Saville on loan from Millwall in the summer. That deal included a clause to make it permanent in January. According to Football.london, the Lions received a club record £8m.
Meanwhile, Stoke City landed Ryan Woods on a similar deal from Brentford. Before the transfer was confirmed, the Telegraph reported that the Potters were prepared to pay £6.5m for Woods.
Those two players are admittedly slightly younger than Fleck at 25-years-old, but not many would argue they’re playing at a higher standard.
Stoke also paid more for a central midfielder who is the same age as the Scotland international. Like Fleck, Sam Clucas is 27, and he was signed from Swansea City over the summer for £6m (BBC).
Not only that, but all three were being signed by Championship clubs. They weren’t deemed good enough for the Premier League, whereas Fleck apparently is.
For all of those reasons £4m seems a woeful undervaluation by West Ham.