Both Championship clubs are on the hunt for a new boss and view Wilder as an option due to an ongoing ownership dispute at Bramall Lane.
Co-owners Kevin McCabe and Prince Abdullah are currently involved in a High Court case to determine who takes control of the Blades.
This has put the future of Wilder into doubt. This is despite the fact he has just lead United to promotion to the Premier League.
Wilder wants assurances over his transfer budget for next season. The 51-year-old is also concerned off-field problems might affect things on it.
West Brom still view Wilder as a viable candidate as their search continues. Chris Hughton was also being considered but would have to take a pay cut after being sacked by Brighton and Hove Albion. Another on the shortlist, Lincoln City’s Danny Cowley, isn’t believed to have tactical methods in keeping with the Baggies.
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Why Middlesbrough want Chris Wilder
Since taking charge in the summer of 2016, the Blades have enjoyed a rapid rise under Wilder. That first campaign they won League One with 100 points, bringing to an end a six-year stay in the division.
The following year they finished 10th in the Championship, before being promoted in 2018/19. Before that Wilder had been promoted from League Two with Northampton Town and the National League with Oxford United.
The Yorkshireman – who is a boyhood Blades fan and former player – has also been praised for his unique tactics. Wilder plays a 3-4-1-2 that sees the overlapping centre-backs often the furthest forwards in attack.
This is in stark contrast to Boro’s last boss, Tony Pulis. Pulis is viewed as an old school tactician and his style lacks goals. Despite finishing seventh last term Middlesbrough had the fifth worst goals tally in the league.