Five-under par won the Irish Open last year, but Australian Richard Green needed only seven holes to reach four-under on the event's return to Adare Manor today.

The left-hander opened with a 10-foot birdie putt and then picked up more shots on the 14th, 15th and 16th to leap into a two-stroke lead over playing partner Rory McIlroy and Swede Johan Edfors.

Conditions were perfect for the early starters and 19-year-old McIlroy, third and fourth within a month of turning professional late last year, birdied the 12th and 13th, while Edfors birdied two of his first three.

Defending champion Padraig Harrington had to settle for four opening pars, missing a seven-foot chance on the long 12th, but his playing partner Graeme McDowell sank a bunker shot for his four there and that made up for a bogey on the previous hole.

Just ahead of them, Colin Montgomerie — whose slip to 88th on the world rankings this week represents his lowest position since October 1990 — birdied the 433-yard 13th and was one-under after five holes.

Harrington tied with Welshman Bradley Dredge last year — they were four clear of third-placed Simon Wakefield — but both the rough and the weather were worse that week and scoring was expected to be lower.