RORY MCILROY may have been called a "badass" by Jordan Spieth, but he will heed Jack Nicklaus' advice to employ a conservative approach as he tries to complete the career grand slam.

McIlroy needs to win the Masters to join Nicklaus, Tiger Woods, Gene Sarazen, Ben Hogan and Gary Player in having claimed all four major titles.

And although Spieth feels McIlroy would have the edge if the pair did battle in the closing stages at Augusta National on Sunday, McIlroy knows limiting his mistakes is key to getting his hands on a green jacket.

Since 2010, the 27-year-old has had more double bogeys or worse at Augusta than any other player under 50, a key factor in shooting a round of 77 or higher in six of his last seven starts.

"If I can make a three on (hole) four and a four on 11 every day this week, I think I'll be okay," McIlroy joked in his pre-tournament press conference. "I think I played those holes nine over par last year.

"Around here, don't take on too much. Actually I had a little conversation yesterday with Jack Nicklaus in Florida. That's what he said. He said to me, 'I took on too much a couple of times and it cost me a couple of green jackets.' I'm like, 'Well, you have six.'

"But he said it is a golf course that can tempt you. It can tempt you into doing a little bit too much.

"I cast my mind back to the 11th hole on Saturday last year where I'm in the pine straw on the left and I'm trying to hit this low hook around and catch the hill and trying to get it up onto the green and hit this heroic shot and it goes in the water and I make a six.

"That's the last thing I needed. I was three or four over for the day at that point and I needed to hit it to the right of the green and try and make my up and down. Even if you make five, five is better than six; take the water out of play."

McIlroy famously lost a four-shot lead in the final round in 2011 after collapsing to a closing 80, while Spieth has his own demons to conquer after blowing a five-shot advantage with just nine holes to play last year.

The 23-year-old American has still finished second, first and second in his three Masters appearances and feels that "strikes fear" into his opponents.

But asked if there were any players that he feared this week, Spieth said: "Yeah, Rory McIlroy. He's been there, done that. The guy is a badass. Can I say that here?

"He's a guy that you know that when you're paired up, he's been there and you don't feel like you have that major championship-winning edge. I don't say I've won the Masters and he hasn't. Trust me, he's certainly capable of it and he'll win at least one."

Despite chasing the career grand slam, McIlroy has enjoyed a relatively quiet build-up to the Masters, with most of the attention focused on world number one Dustin Johnson after his three consecutive wins.

After playing 99 holes in practice over the last fortnight, McIlroy plans nine more on Wednesday before likely missing the traditional par-three contest for the second year running, although that could be disrupted anyway due to bad weather.

"I don't feel like I can fly under the radar anymore, but at the same time it's sort of felt that way to me and it's been nice to be able to prepare and just go about my business and try to get ready for this tournament," McIlroy added.

"I've realised that the more I can get comfortable with this golf course and the club as a whole, the better. The more I can just play the golf course and almost make it seem like second nature to me, the better."

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