Chelsea’s veteran defender Thiago Silva is expected to be sidelined for at least a couple more matches.
He will be unavailable for the midweek FA Cup tie against Barnsley and is also likely to miss the league game against Newcastle on 15 February.
The Brazilian could be back for the visit to Southampton five days later, but even that looks a “very ambitious” target, according to Blues boss Thomas Tuchel.
“For Thiago we are fighting every day. He will for sure be out for the FA Cup,” Tuchel said.
“It will take us some time. It will take us several days. I think Southampton is maybe realistic but it is very ambitious.
“We will do everything and I know Thiago – he will do everything to be ready as soon as possible.
“With a muscle injury you cannot take any risks. When it’s healed it’s healed.”
Meanwhile, Christian Pulisic missed the Sheffield United game because of “family issues”, Tuchel revealed.