Rory McIlroy was battling to avoid just his second missed cut in the Masters on Friday after struggling to an opening 75 at Augusta National.

McIlroy was level par when the delayed first round resumed in perfect conditions, but covered the back nine in three over to fall 10 shots off the lead shared by playing partner Dustin Johnson, England's Paul Casey and South African Dylan Frittelli.

After a short break the players headed back on to the course for round two and McIlroy looked a different player as he birdied the 10th, 12th, 15th and 17th to get into red figures for the first time.

At one under par McIlroy was seven shots off the lead shared by Johnson and Sungjae Im, with Mexico's Abraham Ancer a shot behind alongside Casey, who had yet to begin his second round.

Former champion Danny Willett was also just two shots off the pace after recovering from a double bogey on the 10th, his opening hole, with an eagle and five birdies in the next 11 holes.

Johnson had threatened to put significant distance between himself and the chasing pack when he made light of Amen Corner with birdies on the 11th, 12th and 13th to briefly enjoy a three-shot lead.

However, the world number one then three-putted the 14th and dropped another shot on the 15th after finding the water with his approach before missing good birdie chances on the next two holes.

McIlroy's 75 was his worst opening round in 12 Masters and the only good news seemed to be that he will only have to wait five months to get another crack at joining golf's most elite club as the Masters reverts to its traditional April date in 2021.

The 31-year-old needs to win a green jacket to join Jack Nicklaus, Tiger Woods, Gene Sarazen, Ben Hogan and Gary Player in having claimed all four major titles.

However, none of those players needed more than three tries at winning the final leg of the grand slam, while McIlroy is making his sixth Masters start since winning the Open Championship in 2014.

McIlroy had left himself a testing opening shot from a greenside bunker on the 10th when play resumed and was unable to save par.

The four-time major winner was then lucky to find his ball after a wild tee shot on the 13th and had to take a penalty drop from the undergrowth with the aid of an Augusta National member, but at least remembered his manners.

"Thanks and sorry for getting your green jacket dirty," McIlroy said to the official before pitching back on to the fairway.

From there he hit his approach to 15 feet but was unable to convert the par putt and another shot went following a pulled drive on the 14th.

McIlroy found the green in two on the par-five 15th to set up a much-needed birdie, only to pull his tee shot on the next into the water.

"That's so bad, oh my God," McIlroy exclaimed in exasperation, although he was at least able to salvage a bogey following a mediocre pitch from the drop zone.