Should Johnson emerge the winner he will go back to the top of the world ranking, moving past Justin Thomas who replaced him following his win at the Players Championship.
Johnson added a third round of 65 to his opening rounds of 67 and 63 but it was still not enough to hold off Putnam who is looking for his first PGA Tour title while Johnson has 17 titles to his name, one of those a major.
Putnam was bogey free in his round of 64 and although a previous member of the PGA Tour in 2015 he was required to return to the Web.Com Tour and now appears to be finding his feet at this level. The way he handles the battle with the world number two Johnson tomorrow will be of great interest.
It appears on paper as a one-sided battle but tournament golf works in strange ways and Putnam is an emerging star with two victories on the Web.Com Tour prior to graduation to the bigger stage this year.
It was a day of low scoring with five players recording rounds of 65 or better.
Of the Australians Stuart Appleby continues what has been an encouraging week given his recent horror run to be in a share of 19th place although ten shots from the lead, Aaron Baddeley improved sharply with a round of 67 to be in 29th place and Cameron Percy and Matt Jones 39th.
SIGNATURE HOLES 8TH AT BENALLA
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