Quote from : Harry Potter and the Order of the Phoenix Book

So,” sneered Fudge, recovering himself, “you intend to take on Dawlish, Shacklebolt, Dolores, and myself single-handed, do you, Dumbledore?” “Merlin’s beard, no,” said Dumbledore, smiling. “Not unless you are foolish enough to force me to.” “He will not be single-handed!” said Professor McGonagall loudly, plunging her hand inside her robes. “Oh yes he will, Minerva!” said Dumbledore sharply. “Hogwarts needs you!