But while McIlroy faced an uphill battle to avoid a third straight cut in the event after crashing to an opening 80, Harrington claimed a share of the overnight lead with Germany’s Max Kieffer with an opening 67.

And after starting his second round on the back nine with a run of six pars, Harrington picked up his first birdie of the day on the 16th to move into the outright lead on five under par.

There was not such good news for another home player however, with 2009 winner Shane Lowry having broken his putter as a run of three bogeys in four holes dropped him to four over par.

.@shanelowrygolf's putter in the boot of Neil Manchip's car. Bent the handle slightly on 12. Putting with a wedge. pic.twitter.com/QPyR9Ea5GH

— Brian Keogh (@IrishGolfDesk) May 29, 2015

That was one shot outside the current projected cut, although that seemed certain to rise as more players took to the course, with McIlroy scheduled to start his second round at 1pm.

Harrington holed from 15 feet for birdie on the 17th to extend his lead and missed from just six feet for an eagle on the par-five first, but the tap-in birdie took him further ahead of the chasing pack.

At seven under par the 43-year-old, whose victory in the Honda Classic in March was his first on a major tour since the 2008 US PGA, was three ahead of Kieffer, who had started with two pars, with 2002 winner Soren Hansen, Austria’s Bernd Wiesberger and France’s Alexander Levy all two under.

Lowry bogeyed the 17th but successfully two-putted the 18th with a wedge to reach the turn in 40, his putter understood to have been damaged after he missed a short putt on the 12th.