Rory McIlroy faced an uphill battle to make the halfway cut after suffering a nightmare start to his second round in the US PGA Championship.

McIlroy’s only birdie of the opening day came on the 18th hole and gave the four-time major winner cause for cautious optimism, but that quickly disappeared on the fearsome back nine at Bethpage Black.

Starting on the 10th, McIlroy hacked his way down the 492-yard par-four to card a double-bogey six and dropped another shot on the next following a tee shot into a fairway bunker.

Another wayward drive on the 12th forced McIlroy to pitch out of the heavy rough on to the fairway, but from 150 yards he flew his approach over the green, failed to make the putting surface with his chip and two-putted from the fringe for another double bogey.

McIlroy, whose victory in the 2014 US PGA at Valhalla is his last major title to date, stopped the rot with a birdie on the par-five 13th but at six over par was two shots outside the early projected cut mark.

The cut had also become a concern for New Zealand’s Danny Lee, who began the day a shot behind defending champion Brooks Koepka after a superb opening 64, but covered the back nine in 41 to fall back to level par.

Lee dropped shots on the 11th and 12th and then double-bogeyed the 15th and 16th before gratefully starting the easier front nine with a birdie on the first.

Former Masters champion Danny Willett had birdied the first two holes and bounced back from a bogey on the third, a 221-yard par three playing into the wind, to birdie the par-five fourth and reach one under par.

Koepka, who is seeking a fourth major title in his last eight starts, was among the later starters in a group containing Masters champion Tiger Woods and Open champion Francesco Molinari, who were both nine off the pace after opening rounds of 72.