RORY McILROY expressed his satisfaction after keeping his dreams of the career grand slam on track with a battling display on the opening day.

Seeking to become just the sixth player in history to win all four major titles, McIlroy was one-over-par after 11 holes before recording birdies on the 13th and 15th to card a one-under-par 71.

That left the world No.1 seven shots off leader Jordan Spieth of America, but it could have been a lot worse as the 25-year-old was forced to scramble for par a number of times on the front nine.

"I just kept telling myself to be patient," McIlroy said. "It was a tricky day, the wind was swirling a little bit, the pin positions were tough. Anything under par was a pretty good score. It was nice to pick off a couple of birdies on the back nine on the par fives and I'm pretty satisfied with the day's work."

McIlroy has recorded a score of 77 or worse on each of his past five appearances at Augusta National and admitted it could have happened again.

"It could have been a round that got away from me," he admitted. "I bogeyed 11, but I just kept telling myself to stay patient, realising it's a 72-hole golf tournament and I don't need to press too much. That's what I did and it was good to get into red numbers after day one.

"I feel I'm driving the ball well and if I can keep doing that and just be a little more efficient with my iron play and give myself more opportunities I'll hopefully be right there at the end of the week.

"I haven't put too much pressure on myself. I obviously know what I can achieve this week, but I'm not letting myself think about it too much. I'm just trying to play it one round at a time and yesterday was a pretty good day.

"I feel like I can do better, but I'm happy and I'll go out and try and do a little bit better today."