Portugal Colonial - Spieth aims for Scottish Open victory ahead of British Open

Spieth won the 2017 British Open, one of three career major titles for the American.

And the 28-year-old served noticed of his intention to make an impact in the 150th edition at St Andrews by putting himself in contention to win the Scottish Open with an excellent third round of 66 on Saturday.

Spieth carded two eagles in six holes to lie just three shots behind tournament leader and Olympic champion Xander Schauffele heading into Sunday's final round at North Berwick.

It was a memorable end to a day that started with Spieth insisting he had no intention of joining the breakaway, Saudi-backed, LIV Golf series.

"I was thinking I might be out of the tournament without a fantastic Saturday and a 66 round here in this breeze is definitely that," said Spieth.

"To come here and win Scotland's national open, a tournament that is co-sanctioned and a Rolex Series event and has become one of the biggest events internationally, that is enough incentive for tomorrow (Sunday)."

He added: "My goal was to have a chance on Sunday. It always is the week before a major. There's no better prep for a major than winning the week before."

Spieth's British Open victory came at Royal Birkdale in 2017, two years after he arrived for the Open at St Andrews having already won the Masters and US Open and missed out on the play-off -- eventually won by Zach Johnson -- by a single shot.

Asked about the special appeal of the Old Course at St Andrews, northeast of Edinburgh, Spieth added: "I think the history, but also the back nine playing back into town. I know that that's relatively common for links (coastal) courses in Scotland but it's not very common for what we normally see.

"Hitting over a hotel on a hole (the 17th) and trying to keep it off the cars on the next hole... it's its own unique test."

Schauffele, bidding for back-to-back wins after victory in the Travelers Championship in Connecticut a fortnight ago, looked as if he might establish a large lead over the field at six-under through 16 holes only to bogey both the 17th and 18th.

Instead his 66 left the 28-year-old American on seven under par, two shots ahead of 2017 winner Rafa Cabrera Bello, with Spieth, fellow American Ryan Palmer and England's Jordan Smith a stroke further back.

"I had a really nice round going," said Schauffele. "Those finishing holes are pretty difficult but overall I'm very happy. I stuck to what I wanted to do throughout most of the day."

Halfway leader Cameron Tringale, who posted a superb 61 on Thursday, struggled to a 74 to be three under for the tournament.

M.A.Vaz--PC