Two-time Open Championship winner Padraig Harrington's lowest round in a Major shot him into contention for another Claret Jug, and he believes his experience could be a significant factor on the final day at St Andrews.
The Irishman carded a seven under par 65 to leap to ten under and create a realistic chance of capturing his fourth Major as the tournament heads for Monday finish.
His previous best single-round score was back-to-back 66s on the weekend to win the 2008 US PGA, having also made that score at The Open way back in 2001 at Lytham.
Harrington's first win on a major Tour in seven years came at March's Honda Classic, which also needed an extra day, but it is his memories of getting the job done on the final day of a Major that he will be looking to use on Monday.
"I always wanted to shoot 65 on the Sunday of an Open - obviously there's another round to go tomorrow," he joked.
"I'll be certainly telling myself that I know what I'm doing and I've done it before and I'll be using it to help myself for sure, having done it twice before.
"Clearly things were going well for me today but I didn't want to look up (to the scoreboard) and see somebody getting away and be disappointed.
"When things are going well you might as well just keep your head down and keep going.
"There's no point in looking around and getting distracted. I didn't look until I finished off on 18."
The 144th Open Championship over the Old Course is shaping up to be one of the closest in a long time with the top of the leaderboard tightly packed.
In a week that produces mixed feelings for Harrington - a decade ago his father died and he pulled out of the event at St Andrews, while last year his coach Bob Torrance passed away – the 44 year old insists he will not be wearing his emotions on his sleeve.
"I'm not going to try to get emotionally involved in any shape or form," he added.
