A Pressman error gave Sunderland all 3 points, when Stephen Caldwell’s 69th-minute header slipped past his grasp.
Earlier on in the game, David Connolly put two shots wide, and Keith Gillespie went close.
Leicester: Pressman, Canero (Dublin 85), Dabizas, Heath, Stewart, Gillespie (Morris 60), Nalis, Gudjonsson (Gemmill 72), Tiatto, Scowcroft, Connolly.
Subs Not Used: Makin, Keown.
Booked: Dabizas, Tiatto.
Sunderland: Myhre, Lynch (Lawrence 72), Breen, Caldwell, Arca, Whitehead, Robinson, Whitley (Danny Collins 89), Carter, Elliott, Stewart (Brown 62).
Subs Not Used: Bridges, Carson.
Booked: Breen, Stewart, Robinson, Whitehead.
Goals: Caldwell 69.
Ref: C Penton (Sussex).