Johnson has recorded rounds of 69, 68 and 66 to set up a second win in the event having won in 2013 and finished inside the top then in his three starts since.
Rickie Fowler and Jason Dufner are tied for 4th another shot further back.
The news was not so good for Australia’s Marc Leishman however who struggled to a 3rd round of 76 to fall to 12th place after taking a share of the lead with Harman into round three.
Cameron Smith, the only other Australian in the field, would, though, continue his recovery from a slow start to the tournament to now be in a share of 17th position after a round of 68 today, a 5 under par back nine of 32 moving him quickly through the field.
Johnson took control of the event with a whirlwind finish to his third round beginning with a pitch in for eagle at the par 4 12th followed by birdies at the 14th, 15th and 18th while Harman, too, finished strongly with birdies at three of his last four holes to finish the day in clear second position.
JAIME GLAZIER THE MIND'S EYE
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