A somewhat frustrated Jordan Spieth is hoping for a rare "stress-free" finish at the Masters after a disappointing day three at Augusta.

The 24-year-old, along with world number one Dustin Johnson, struggled to keep pace with Patrick Reed and Rory McIlroy at the top of the leaderboard, with each mustering a one-under round of 71.

Spieth bogied the fifth and ninth holes and his unfortunate round was compounded on the 17th, when the ball dipped inside the hole before bouncing out to deny him a birdie.

With Reed nine shots in front, the 2015 champion is now looking forward to a final day of unusually reduced pressure.

"I did everything I felt I could do," he said. "I had a lot of really good chances and it just wouldn't go in for me. And that happens sometimes. 

"I did a lot of things really well and there was just a lid on the hole. So, I'm not down. I get to go out for one of my only stress‑free rounds that I've ever really played at Augusta National and enjoy the walk.

"And then we'll go try and do what some of those guys did out in front today, shoot seven or eight under."

Johnson, a stroke further back after a round that included a double bogey on the 11th, was equally frustrated with the outcome of his efforts on the greens.

"I thought I hit it beautifully today, a lot of good putts," he said. "Just nothing went in the hole. I couldn't get anything to go."

With the green jacket now effectively beyond his reach, Spieth is relishing the prospect of a final-day showdown between Reed and McIlroy, who is three shots off the pace in second.

"Patrick is somebody who isn't afraid of challenges, obviously, as we've seen in the past," he said. "It's been kind of a major championship hump that he's had to get over and play the way that he knows how to play. So, I'm not surprised. It was kind of a matter of time, I thought. And he's been progressing nicely and gaining confidence every week.

"I think he's come in with the mentality that he's fully capable of winning here, and he's proving what he is capable of doing here.  It's going to be a pretty cool showdown with Rory, maybe with a couple back now."