Darren Clarke lies six shots behind leader and compatriot Rory McIlroy after firing a first round of level-par 72 at the Open Championship at Hoylake.
The 2011 champion posted four birdies, two bogeys and a double bogey.
Graeme McDowell faces a battle to make the cut after carding a disappointing two-over 74, which included a double bogey seven at the 10th hole.
Michael Hoey is one shot worse off after recording two birdies and five bogeys in his round of 75.
Hoey, who qualified for the championship by finishing seventh at the French Open, registered successive bogeys at the 13th, 14th and 15th holes.
McDowell signed for two birdies and a bogey on his front nine, but his round was marred by a further bogey at the 13th, as he ended the day in a tie for 84th position.
Padraig Harrington, winner in 2007 and 2008, joins McDowell on two over.
Ex-Irish Open champion Shane Lowry was among the afternoon starters and his round of 68 saw him finish the day in joint third on four under.
Amateur qualifier Paul Dunne shot a creditable 75 to join Hoey in tying for 105th place.
Clarke is tied for 49th ahead of Friday's second round.
McIlroy enjoys a one-shot advantage over Italian Matteo Manassero at the top of the leaderboard.