Sunderland midfielder Vaughan admits O'Neill furious over Blackburn defeat
Vaughan, however, is confident they'll bounce back after a disappointing night at Ewood Park.
Vaughan told The Journal: "It was a very bad night at the office. The manager told us one or two things he wanted us to put right. I think it was the maddest I've seen him.
"He wasn't very happy but that's understandable because he has set very high standards for us. Now it up to us to put things right and show what we're really about."