World No.1 Rory McIlroy has taken charge at the season’s final major, claiming the clubhouse lead midway through a wet second round of the PGA Championship at Valhalla Golf Club.

The Northern Irishman, winner of the British Open and World Golf Championship’s Bridgestone Invitational at his past two starts, carded a four-under 67 to push out to eight under par and a two-stroke lead from American Ryan Palmer (70).

Overnight co-leaders Lee Westwood and Kevin Chappell sat tied third as they started their rounds.

Starting on the back nine McIlroy had an early bogey on the 12th hole, his third, but bounced back with birdies at 13 and 15 to be heading in the right direction.

The 25-year-old then really started humming with an eagle on the 18th, his ninth hole, dropping a 31-foot putt to take a two-shot lead.

A bogey on the second hole reduced his cushion to just one shot and Palmer joined him at the top for a moment but a birdie on the seventh, his 16th, sent McIlroy back in front alone.

A finishing-hole birdie put the exclamation mark on the three-time major winner’s tilt.

Matt Jones, Jason Day and Geoff Ogilvy lead Australia’s charge at two under par.

Jones has one hole to play in his second round, Ogilvy has four while Day has just started his second round.

Jones bogeyed the second hole but dropped birdies on the fifth and eighth holes to be right in the mix before bogeys on the 10th and 17th holes hurt his charge.

Ogilvy has two birdies and two bogeys in his first 14 holes.

Adam Scott and Marc Leishman head out at even par, the current projected cut line.

Club pro Stuart Deane’s dreams of making the cut were dashed after he finished at four over but he did well to shoot 71 in round two.

Steven Bowditch (+5 through 15 holes) and John Senden (+7) are heading to an early finish.