Darren Clarke went on a birdie chase as he made his European Tour debut in Morocco yesterday.
The Dungannon man recorded seven birdies and four bogeys for a 69 at the Hassan Trophy.
Ireland's Peter Lawrie carded a six-under round of 66 to lie just one shot behind early pacesetter Nick Dougherty.
There were contrasting fortunes for another two Ulstermen. Ballyclare player Gareth Maybin opened with a 71 but Michael Hoey crashed to a disappointing 80 to finish seven over par.
Also off the pace are Shane Lowry (74), Damien McGrane (75) and Paul McGinley (76).
Lawrie and Clarke were playing their opening rounds on the shorter Blue course at Royal Dar Es Salam in Rabat.
Meanwhile, given a decent lie-in after returning from Wednesday's flying visit to the White House at half past midnight, Padraig Harrington opened the Transitions Championship in Fort Lauderdale with a solid two-under-par 69 yesterday afternoon.
Harrington, who presented President Barack Obama with a set of left-handed Wilson clubs and a golf bag with the Seal of Office emblazoned on it, wielded his own irons with aplomb on the challenging 7,340-yard Copperhead Course, despite playing just one practice round.
After getting up-and-down capably for par on the first two holes, Harrington hit the next nine greens in regulation, eventually sinking a sensational 37-foot putt for eagle three at 11.
He followed that up by landing a birdie from the fringe rough at 12 with a deft flick of his 9-iron. Though his putter let him down at 13 and 17, where he missed from inside six feet for par, Harrington holed out from a greenside bunker at the last to finish four behind clubhouse leader Garrett Willis who shot 65.
It wasn't such a good day for Ian Poulter, however, who is in a fight to survive the halfway cut in his last Tour event before next month's Masters. The World Match Play champion managed only a two-over-par 73.
That was eight shots adrift of Willis, who led by two from fellow Americans Jeff Maggert, Jim Furyk, Jonathan Byrd and also defending champion Retief Goosen.
Poulter, who matched the best round of the week with a closing 64 at the WGC-CA Championship in Miami on Sunday, dropped a stroke on his opening hole and followed birdies at the 11th and 17th with a bogey each time.