The duo, who have both been promoted to the Premier League, are among five clubs interested in Vaulks. The Blades’ rivals Sheffield Wednesday are also keen, as are playoff finalists Derby County. Recently relegated Cardiff City complete the quintet.
Vaulks greatly impressed with his performances for Rotherham in 2018/19. Yet it wasn’t enough to keep them in the Championship.
The Millers will be playing in League One next season following their relegation and the club have accepted the 25-year-old will move on.
The sale of Vaulks is made more likely by the fact the Wales international is about to enter the final year of his current contract.
Who is Vaulks?
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Born on the Wirral, the midfield ace came through the Tranmere Rovers academy. However, Vaulks never made a senior appearance at the club, spending time at non-league Workington before leaving for Falkirk in 2013.
The former Tranmere man spent three-and-a-half years in Scottish football, helping Falkirk to two playoff finals during that time. Vaulks played 142 times for the club.
In the summer of 2016 he returned to England, arriving at the New York Stadium. That first year Rotherham were relegated from the second tier of English football, but Vaulks helped them bounce back at the first attempt via the playoffs.
Despite a valiant effort this term, the Millers once again finished in the bottom three. Vaulks has currently played 137 times for the Yorkshire side, scoring 17 goals.
Although he plays primarily as a defensive midfielder, the Welshman scored eight times and provided seven assists this term. Vaulks also showed his leadership skills and was often captain.
While often used in midfield, his versatility means he can also play as a central defender. Vaulks also made his Wales debut in March. He has two caps to date.