He knows it will take something “pretty perfect” but Cameron Smith’s quest for the 149th Open Championship remains alive after a round of two-under 68 at Royal St George’s on Saturday.

For the third straight day it will be South African Louis Oosthuizen (69) at the top of the leaderboard at 12-under par when play begins on Sunday night, AEST, holding a one-stroke advantage over 2020 PGA champion Collin Morikawa (68) and three strokes clear of 2017 Open champion Jordan Spieth (69), who made bogey at both of his two closing holes.

Smith will start Sunday six strokes off the lead in a tie for ninth yet with the belief that if he can produce something special, his hopes of becoming just the fifth Australian to win The Open championship have some life left within them.

“It’s going to take a big one tomorrow,” conceded Smith, who will tee off at 10.55pm, AEST, alongside South African Justin Harding.

“Course is firming up nicely. Still not unplayable, birdies are still there, but it’s going to have to be pretty perfect I think.

“Louis and Jordan at the top of the leaderboard, two great competitors, they’ll be tough to catch.”

Where he had struggled on the opening hole the first two days – and with the tee shot in particular – Smith made the ideal start to his third round, finding the green with his approach shot and holing his birdie putt from just outside 10 feet to reach five-under.

Where he had found birdies hard to come by early in his round the first two days Smith went back-to-back at the par-3 sixth and par-5 seventh, making the turn in three-under and with momentum at his back.

That momentum took a hit with consecutive dropped shots at 10 and 11 but he snared his fourth birdie at the day at the par-5 14th, gave it back at the next but kept the flame of hope flickering with a brilliant birdie at the final hole.

“It was really, really solid today,” said the 27-year-old. “Probably the best ball striking day of the week.

“Just a couple of drives there on the back nine… Got unlucky a couple times there.

“You know, that’s just links golf. Just kept at and kept trying to make my birdies and carry on.”

Australia’s only other chance entering the weekend, Adam Scott, endured a difficult day three as he fell to a tie for 58th with a round of three-over 73.

In truth, Scott didn’t do a lot wrong but a double-bogey six at the fourth when his first putt from the front of the green failed to climb the enormous mound on the left and rolled back behind the spot from where he had just putted was an early gut-punch.

He got one of those strokes back at the next but after 12 straight pars a second double bogey on the final hole was a sour way to sign off his Saturday round.

Kiwi Ryan Fox also travelled in the wrong direction on the leaderboard on day three, falling eight spots to be tied for 25th after a round of one-over 71.

It was in fact a strong fightback from Fox after he tangled with the rough twice on his opening two holes to start bogey, double bogey, making birdies at seven, eight, 11 and 14 before another double bogey at the par-4 15th.

“Unfortunately it was just one of those days where for the most part if I hit a bad shot I got hammered,” said Fox.

“But I hit a lot of really good shots today, I putted it nicely, so there are some positives to take into tomorrow.

“So 1-over on a day like today, yes it probably takes me out of contention for the tournament, but it doesn’t take me out of contention for a decent finish.

“I just need to keep it in play a little better tomorrow and hopefully everything else stays how it is and I’ve got a good shot.”

The Champion Golfer of the Year at St Andrews in 2010, Oosthuizen was eyeing off a three-round total up towards 15-under when he reached 13-under at the turn. But bogeys at 11 and 13 invited both Spieth and Morikawa to enjoy a share of the lead before a superb tee shot at the par-3 16th set up birdie and the narrowest of leads through 54 holes.

Runner-up in both of the two most recent Majors – the PGA and US Open – Oosthuizen has vowed to give it his all so that he doesn’t find himself in the same position on Sunday night.

“Finishing second isn’t great, so I will play my heart out tomorrow and see if I can lift the claret jug again,” said the 38-year-old South African.

“You need to believe that you can lift the trophy, as well. If you think about it beforehand that you might win this championship, I think that’s great, and you have to believe you can do it.

“I’ll be watching the leaderboard out there tomorrow afternoon and see how it goes.

“Having a lead with two, three holes around this golf course, if you hit a poor tee shot, you’re in trouble.

“A lead is not like you can just hang tight and just hit a few shots coming in. You need to still play proper golf and place the ball really well to avoid bogeys.”

Morikawa can make history by winning a second major in his first attempt and says he will draw on the good shots he has played through the first 54 holes to apply some Sunday pressure to Oosthuizen.

“I don’t have much experience on links golf,” conceded Morikawa, appearing in The Open for the first time. “Pretty much all the highlights in my head are from this week. Thankfully there are quite a few.

“It’s going to be a gruelling 18, but I look forward to it.

“It’s position you want to be in. As an athlete, golfer, you want to be in this position. I love it, so I really look forward to tomorrow.”