Novak Djokovic is ready to fight for his world number one status as Andy Murray heads into next week's Paris Masters looking to overtake the Serb.
Murray, 29, won his third title in as many weeks with victory in Vienna on Sunday and could top the rankings with another good run in Paris.
Four-time champion Djokovic says he is rejuvenated after a slump in form.
"It makes me want to go on court and fight for every point because there is something to win at the end," he said.
The 12-time Grand Slam champion returns to action after losing in the Shanghai semi-finals two weeks ago.