A determined Scunthorpe outfit made Manchester City battle all the way before going down 4-2 at home in the FA Cup Fourth Round.
The class of Manchester City eventually told, but only after they had been pushed all the way by the Championship team.
Martin Petrov smashed in the opener after only three minutes but The Iron's refused to buckle and deservedly levelled just before the half hour through Paul Hayes volley, despite a hint of offside.
But the host's failed to go in at the break level as Nedum Onuoha slid in a second.
Sylvinho hammered a third to give City a two goal cushion just after half time.
Dedryck Boyata's own goal reduced the deficit and set up a frantic last twenty minutes until Robinho eased City's nerves with a late clincher.
How ironic it would be, if as reported, this was to be the Brazilians last game for City.