Sungjae Im holds a one-shot lead after a five-under-par 67 in the first round of the Masters, with Rory McIlroy and Shane Lowry on one-over.
Im carded five birdies - including three in a row to start the round - two bogeys and an eagle on the par-five 13.
The South Korean ended the day with a one-stroke lead over Australian Cameron Smith, who finished on four-over after a double bogey on the 18th.
McIlroy was among the final group to get their tournament underway and a faltering finish to his round saw him bogey two of the final five holes to finish on one over par.
Lowry also carded a first-round 73 after his fortunes oscillated wildly between the 13th and 15th holes, the Clara star recording an eagle-birdie combination before carding a double-bogey seven on the 15th after finding the water.
"Hopefully that's my bad round out of the way and hopefully I can shoot three better rounds than that," Lowry told RTÉ Sport’s Greg Allen.
"If I do that, I think I’ll do okay this week.
"With the forecast for Friday and Saturday, the course will dry out and that will make it tricky.
"I need to sit back with Bo [Martin] and Neil [Manchip] and look at how the day went. It’s easy to stand here and be disappointed with how that finished [double bogey at 15].
"I think if I look at it, I played some really nice golf in amongst a few bad shots. I got really punished for the bad shots."
Padraig Harrington and Seamus Power are a shot further back after rounds of 74.