Nigel Clough was full of praise for his two central defenders following Saturday's FA Cup stalemate at Crewe.
Chris Basham replaced Paddy McCarthy alongside Jay McEveley at the heart of United's back four at Gresty Road and their performances didn't go unnoticed by the Gaffer, who remarked:
"Chris and Jay were excellent and limited a Crewe side that have only lost once recently to very little.
"Our supporters perhaps look at the table and see they are bottom of the table, but on their day they are a capable team and a dangerous one, especially at home."
United, who will be ball number 21 in Monday's second round draw, televised live on BBC Two from 7pm, remain competitive in four competitions, something that pleases Clough, who also spoke about the impact Diego De Girolamo had at the weekend and the enforced absence of James Wallace.
The Blades boss added: "We are still in all the competitions from the start of the season and we are in mid November, that is an achievement to be proud of in itself.
"Diego looked bright when he came on, he needs to improve on certain aspects of his play, but he is full of confidence having scored goals at York and we thought he might nick one for us as the game progressed.
"He comes into contention to start at Walsall, but we will mix and match things for that tie.
"James Wallace had picked up another muscle strain, but hopefully he will be back available for Doncaster."