Guzan's poor clearance undid some good early work by Villa at Chelsea last week, allowing the champions to take the lead and eventually win 2-0 at Stamford Bridge.
That was Villa's seventh league defeat in eight matches, left them second from bottom with four points from nine games and heaped more pressure on Sherwood, who is favourite with leading bookmakers to be the next manager to lose his job.
His side host an out-of-form Swansea City side on Saturday, and Guzan is likely to retain his place for a fixture that could be vital to Sherwood's job prospects.
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"Brad Guzan knows he had made a mistake. But we're all in it together. No-one is the villain," Sherwood told reporters.
"I am sure Brad Guzan has the confidence to put it right."
However, Sherwood did suggest that he will not be afraid to make a change.
"Goalkeepers can only play one position. Mark Bunn will be considered. When it's right to make the change, I will make it."
Sherwood remains upbeat despite his side's dire start to the campaign and said he has had no conversations with either owner Randy Lerner or chief executive Tom Fox about his future.
"I didn't speak much to them when we were doing well last season. That's not unusual," he said.
"It's obviously a transition period. I am proud to be Aston Villa manager.
"I will give everything to the cause. I can't give any more than I am giving, We will get through it.
"We will need Villa Park bouncing tomorrow. We need the help of the fans."
(Reporting by Martyn Herman. Editing by Patrick Johnston)
