Augusta - Jordan Spieth, Masters Champion in 2015 and runner-up in 2014 and 2016, knows as well as anyone that Augusta National's greens are not for the faint-hearted. 

Fortunately, the 24-year-old Texan has shaken off the spectre of a first-round 76 at the Valspar Championship and gained some confidence in his game. 

"I made big strides in the last two weeks to get from a kind of a panic place to a very calm, collected and confident place," Spieth said Tuesday. "It's difficult to do in two weeks. Sometimes it takes years. And I feel like I've been able to speed that process up a lot over the last couple weeks." 

Spieth's disastrous Valspar outing, where he opened with a 76 on the way to a missed cut, was a low-point for the three-time major winner, who had thought he was turning the young season around. 

Spieth has ranked in the top 20 in putting on the US PGA Tour in three of the last four years, but he's 185th in strokes gained putting so far in 2018, a campaign that got off to a slow start after he battled illness in December. 

"It has not been the greatest start to the year of any that I've had," said Spieth, who admits impatience to improve worked against him in the early going. 

But he's feeling better coming into the first major of the year than he did in both 2014 and 2016, when he missed the cut in his last tune-up event, the Houston Open. 

This year, Spieth fired a final-round 66 in Houston to finish with a share of third, a result he called "a tremendous stepping stone in the right direction." 

"I pretended like I was tied for the lead, even though I figured I was a stroke or two back," he said. "I wanted that 'you need to make this' feeling. And I started to really roll some putts in under the gun." 

It was just what he needed before taking on the yawning greens of Augusta, with their lightning-fast surfaces and treacherous break. 

Spieth, however, said he finds the difficulty of the Masters greens somehow freeing. 

"You just have to have a lot of feel," he said. "When I see these greens, my first thought isn't where does this putt go. My first thought is, what's the speed that's needed on this putt. 

"For whatever reason, that has been beneficial to me when I focus just on what speed does this need to get in. I find myself not worrying about the line and therefore not worrying about the mechanics."