Shane Lowry is just four strokes off the pace at the Travelers Championship after carding a bogey-free round of 64.
The Offaly man birdied five of the opening nine holes and added one more birdie on the back nine to sit four shots behind America's Denny McCarthy, who took the opening round lead with a blistering 60.
Meanwhile, Rory McIlroy picked up his first ace on the PGA Tour, with the Holywood man’s hole-in-one on the 214-yard eighth the clear highlight on a mixed session for the US Open runner-up, who finished two-under-par on a day of low scores.
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It was McIlroy’s first ace in competition since he made one in Abu Dhabi on the European tour in 2015.
Meanwhile, McCarthy shot the lowest round of his career after setting a blistering early pace with four straight birdies to open his tournament.
He added five more without dropping a shot en route to a score of 10-under-par.
He leads by two from compatriot Keegan Bradley and Australian veteran Adam Scott.
