MIAMI (AFP) - World No. 1 Jordan Spieth heads into his Valspar Championship title defence hoping another solid showing at Innisbrook will boost his momentum for the Masters.

The 22-year-old Texan's playoff triumph on Innisbrook's Copperhead course in Palm Harbour, Florida, last year was the first of five PGA Tour wins in 2015 that included two Major titles and propelled Spieth to the top of the world rankings.

He admitted on Wednesday that after launching 2016 with an eight-shot victory in the Tournament of Champions in Hawaii, he had put expectations on himself that were "too high".

He went on to finish fifth in his debut in a regular European Tour event in Abu Dhabi and second in Singapore before missing the cut at the Northern Trust Open in Los Angeles.

He wasn't a factor in last week's World Golf Championships event at Doral.

"We've had a win this year already, but obviously the last few PGA Tour events weren't up to par with how we were doing before," Spieth said.

But he noted that he was still ahead of where he was at the same point in 2015, and with characteristic calm he said he would continue to try to build methodically toward his title defence at Augusta National next month.

"All I'm looking to take out is some momentum from what was strong and to build on what I need to do to improve from last week and I'll be ready to go," Spieth said. "I'm looking at it from the face we've already won this year, so now it's time to build this momentum right into this Major.

"Obviously you want to set high-end, borderline unrealistic expectations for yourself because if you get anywhere close to it you're going to be there. But there's a balance that I need to find. It has been a learning experience this year."

Spieth said one thing largely missing so far this season is success on the greens.

"Really need to get my putter going," he said. "They haven't quite gone in yet - but they will."

Spieth will play alongside Henrik Stenson and Bill Haas in the first two rounds.

Stenson, who had six runner-up finishes worldwide last year, finished one shot outside the three-man playoff among Spieth, Patrick Reed and Sean O'Hair at Innisbrook.

"I think it's a good golf course for me," said the Swede, who had knee surgery in December and has opted out of the WGC Match Play in two weeks to rest for the Masters. "I played it for the first time last year and got to hit some good iron shots into the greens and that seems to suit my game pretty well.

"A win at the right time is definitely huge for your confidence and why not make it here? It kick-started last year for Jordan and I wouldn't mind getting a win.

"It's been a little while and I came close a few times last year so I feel like I'm ready for one."