The 2-2 draw with South Yorkshire rivals Barnsley at Bramall Lane was the final nail in the coffin and means the Blades can no longer overhaul Doncaster or Crystal Palace with one game of the season remaining.
It had looked as if the great escape might be on as they led for much of the second half after goals from Matt Lowton and Lee Williamson cancelled out Danny Haynes' early opener.
But Haynes struck again late on to earn a point for the Tykes and condemn the Blades to the third tier of English football for the first time since 1989.
"I'm not Mystic Meg, I don't know," he said when asked whether he'd remain in charge at Bramall Lane. "I think there'll be a meeting of minds and I am sure everything from top to bottom will be discussed. Relegation is a low point, devastating, but I want to be the manager that brings the club back this time next season to Championship.
"The implications of relegation will be felt and there will be a certain amount of cutting your cloth accordingly so it will be an interesting summer."
Source: PA
Source: PA