Three back at 6-under resides a trio of players, including Thomas Bjorn, Roger Wessels and Robert Karlsson, while overnight leader Dean Robertson carded a second round of 74 to join Greg Norman and three others at 5-under-par 139.
While O'Hern went around the Vines Resort course in 66 Thursday, it was Tinning's turn to do the same on Day 2. And had it not been for a flury of birdies late in his round, he might not be sitting so pretty following the opening 36 holes; the 38-year-old went out in 5-under on his back nine, which included birdies over his last four holes.
'I am hitting the ball well and have been ever since I arrived here on Tuesday,' said Tinning, who won for the first time on the European Tour at last year's Wales Open. 'But I didn't know I was going to have this good a round.'
'I made some putts coming in and finished with four birdies, which turned a good round into a superb round.'
On the converse side, Australian-born O'Hern did all his scoring on the front side, which began at the tenth. He was 3-under at the turn, but could do no better than a string of nine consecutive pars over the closing holes. Yet, he remains in good spirits for the weekend.
'The course is playing fantastic, the fairways are very tight, and the greens are running nicely, it's going to be a good weekend,' he said.
Local hero Norman was certainly shaping up to have a great weekend, coming off one of the better rounds he has turned in as of late. Following a fine showing of 66 in the opening day, however, the Shark could do no better than a 1-over 73 Friday. Yet, at 5-under, he is only four shots back, which is where the 47-year-old has traditionally been most dangerous throughout his career.
And on one final note, three fine players who are just in the infancy of their careers in the professional ranks got a taste of of over-par golf as well Friday, as Justin Rose, Charles Howell and Adam Scott shot respective rounds of 75, 73 and 77.
While Rose and Howell made the cut, which came at 1-over 145, Scott (the only one of the three who has won professionally thus far, at the Alfred Dunhill Championship) will have to go home for the weekend.
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