J World No.8 Jason Day is attempting to apply some heat in the final round of the US PGA Tour Tournament of Champions, rocketing into the top five midway through his round.

Day has six birdies in his last seven holes to be 15 under for the tournament with seven holes to play.

He is now fifth but still four shots back of American leader Jimmy Walker.

Walker has moved to 19 under for the week through just four holes of his final round, two shots clear of playing partner Hideki Matsuyama.

Brendon Todd and Patrick Reed hold third at 16 under through five holes.

Day opened with four pars before catching fire.

He slotted a short birdie putt home on the fifth, dropped a 20 footer into the cup on the sixth, doubled it with a 40 foot effort on the seventh before coaxing in a 12 foot birdie on eight to announce himself a potential contender.

A missed opportunity to birdie the par five ninth followed but not to be deterred he wedged to three-feet on the 10th and then put away a seven-foot chance on the 11th.

Matt Jones is the next best Australian at 12 under in a tie for 12th, while Steven Bowditch (-9), John Senden (-8) and Geoff Ogilvy (-5) are towards the back end of the 34-man winners only field.