The FA Cup dream was ended but United came away from the Riverside in February 2008 with heads held high after Middlesbrough netted a fortunate extra-time winner.
In front of the TV cameras, the Blades held their Premiership opponents for more than 200 minutes in the fifth round tie before the home side accepted a great slice of luck.
Mido's shot took a huge deflection off Chris Morgan and the ball came back off a post before striking Paddy Kenny and trickling over the goal-line in the second period of extra-time.
Boro: Schwarzer, Young, Arca (O'Neil 77), Pogatetz, Boateng, Mido, Rochemback (Johnson 104), Alves (Tuncay 73), Downing, Hines, Grounds.
Unused: Turnbull, Cattermole.
Blades: Kenny, Naysmith, Morgan, Beattie, Stead (Martin 59, Shelton 90), Speed, Kilgallon, Tonge, Sharp (Hulse 73), Geary, Quinn.
Unused: Armstrong, Ehiogu.
Referee: P Walton
Attendance: 28,108