Less clear was referee Phil Dowd's decision not to award a spot-kick when Johnny Evans pulled Hreidarsson back in the box late in the half.

BBC: Portsmouth 1-0 Sunderland

But Ferguson insists the return to fitness of a number of defenders such as Rio Ferdinand and Johnny Evans will provide his side with the perfect fillip during the title run-in.

BBC: Sir Alex Ferguson fires warning to title rivals

The radio version of this story was produced by Kate Davidson and recorded by Johnny Vince Evans.

NPR: The 'Fabulous Lunts,' Alive at Ten Chimneys

Evans' low left-footed shot was parried by Derby goalkeeper Stephen Bywater and summer signing Johnny Ertl pulled his effort wide moments later.

BBC: Sport - Football - Derby 0-1 Sheff Utd