Shane Lowry described Saturday's stunning round at an electric Royal Portrush as his "most incredible day" on a golf course as the Irishman took control of the Open Championship.

Lowry's blemish-free 63 means he almost has one hand on the Claret Jug, boasting a four-shot lead over Tommy Fleetwood at the summit.

The crowd in Northern Ireland lent their significant backing to the 32-year-old as he pulled clear of a stacked field of contenders to emerge as the clear favourite for the title.

He closed his round with three birdies from the last four holes and Portrush erupted in joy as he left playing partner and overnight co-leader J.B. Holmes six strokes adrift.

"Honestly, that's the most incredible day I've ever had on the golf course. I honestly can't explain what it was like," said a beaming Lowry.

"I said to Bo [caddie Brian Martin] 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'.

"And that's what I did. The crowd was incredible. I just can't believe what it was like.

"I can imagine it was quite difficult for J.B. to play with that. But I found it OK, anyway."

Lowry has never won a major but he does have experience of holding a four-shot lead going into the last round of one.

He did so at Oakmont in 2016 and shot a 76 on the final day as victory slipped from his grasp, but he claims to have learned from that.

"I said to Bo when I finished, look at the leaderboard, four ahead. I said to Bo, 'At least I won't have to answer any questions about Oakmont, I'm four ahead going into the final round of a major'," Lowry joked.

"Obviously I learned a lot that day. I learned a lot about myself at Oakmont. I'm going to learn a lot about myself tomorrow [Sunday].

"I think 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.

"You never know what can happen."