Portrush, Northern Ireland (CNN) The roars for Shane Lowry were just different. Deeper, more throaty, more heartfelt.

With no Northern Irishman in contention, the Royal Portrush crowds have taken Ireland's Lowry to heart and how it has inspired him.

They roared and chanted and clapped and waved as he walked onto the 18th green Saturday, having left the field trailing in his wake on day three of the 148th Open

It had been a truly masterful display, as the 32-year-old from County Offaly fired a stunning 63 to surge to 16 under and take a four-shot lead into the final day Sunday.

The world No.33 will play in the final group alongside English Ryder Cup hero Tommy Fleetwood, who shot 66, with American JB Holmes two further back at 10 under.

Shane Lowry set a course record for the updated Dunluce course of 63 Saturday.

The bearded Lowry has missed the cut in his last four Open Championships, but he has tapped into a special source this week.

He grinned and shook his head as the roars punctuated the still Portrush air as he forged clear while the pack shuffled constantly behind him.

The Open hasn't been to these parts in 68 years and the local fans were determined to make the most of the occasion.

"That was the most incredible day I've had on a golf course," he told reporters with a twinkle in his eyes afterward.

"I just wanted to keep making putts to hear those roars."

At one stage he told his caddie Brian "Bo" Martin, who is from Ardglass, an hour or so to the south, to make the most of it.

"I said to Bo walking off the 17th tee, 'We might never have a day like this on the golf course again. So let's enjoy this next half hour.'"

Shane Lowry was serenaded as he walked on to the 18th green.

'Roaring in your face'

Lowry was serenaded with the European Ryder Cup chant "ole, ole, ole" as he walked up the 18th, and the party songs, with his name added to the lyrics, rang out over the course long after he'd left the arena.

The soundtrack was still going as Lowry began his press conference, but he says he won't get rattled by the intensity of the crowd's support Sunday.

"Honestly, walking from the green to the next tee, the people are literally a yard away from you roaring in your face as loud as they can," he said.

"I thought I dealt with it very well and hopefully I do the same Sunday."

Lowry's previous best finish in a major was at the 2016 US Open at Oakmont, when he led by four after three rounds but collapsed on the final day with a 76 to finish behind Dustin Johnson.

He was asked about that Friday night, and said he's a "totally different person now."

When the same question came Saturday, Lowry laughed. "I was waiting for that."

"I learned a few things that day about playing in the final round of a major with a lead, that you need to just hang in until the very last minute," he said. "You never know what can happen."

Sunday's weather forecast is for rain and strong winds later, causing Open organizers to move the tee time forward by a couple of hours.

Lowry doesn't believe the bad weather gives any of the leaders any particular advantage, and added: "There's a good leaderboard behind me.

"There's no point in saying to go out and enjoy myself because it's going to be a very stressful and very difficult day.

"So I'm going to take the bad shots on the chin and I'm going to take the good shots and try to capitalize on that."

'We're not robots'

England's Tommy Fleetwood will start Sunday two shots behind Shane Lowry.

Later in his relaxed press conference, Lowry was asked how he will prepare Saturday evening at the house he is renting with his family and friends.

"I'd been lying if I said Love Island wasn't on TV," he grinned, before adding: "I'll go to bed thinking about holding the Claret Jug tomorrow evening.

"It's only natural, isn't it? We're human. We're not robots. We can't not think about things. And when you try not to think about something you end up thinking about it more, so you might as well talk about it."

Looming large -- albeit seven strokes back -- in a tie for fourth is world No.1 Brooks Koepka.

The American has won four of his last nine majors and finished second, first, second in majors this year.

He is well aware how quickly big leads can vanish after losing a seven-shot advantage before winning the US PGA at Bethpage in May.

"The last time Shane had the lead at Oakmont we saw that," he said, bringing up Lowry's misfortune.

Fleetwood has also finished second in a US Open -- behind Koepka at Shinnecock Hills in 2018 -- and says he will relish the challenge.

"The atmosphere for us as golfers was just great," he said. "I loved it. For or against you, you can't help but appreciate and love what today was and what Sunday is going to be. it's going to be a very special day."