Serena produces stirring comeback to make semis

MELBOURNE (Reuters) - Defending champion Serena Williams produced a remarkable fightback from a set and 4-0 down against Victoria Azarenka to reach the semi-finals of the Australian Open on Wednesday.

The world number one, initially bullied by the seventh seed from Belarus in their quarter-final, came through 4-6 7-6 6-2 and will meet China's Li Na for a place in the final.

Li had earlier knocked out Williams's older sister Venus on Rod Laver Arena.

Serena appeared sluggish until Azarenka held serve to take her 4-0 lead in the second.

That seemed to finally wake up the top seed who won five straight games to take the set before she blowing the 20-year old off court in the decider.

(Reporting by Greg Stutchbury; Editing by Alastair Himmer)