Rory McIlroy makes strong start at US Open as Adam Hadwin leads

Rory McIlroy was among the five-man pack sitting one shot back of Canada's Adam Hadwin after the first round of the US Open on Thursday as Phil Mickelson struggled a week after making his controversial LIV Golf debut.

Mickelson shot an eight-over par 78 to sit near the bottom of the 156-player field at The Country Club.

A record six-time US Open runner-up, Mickelson's self-imposed four-month hiatus following comments he made about the LIV circuit and PGA Tour was evident in the opening round.

Mickelson, who struggled on the greens all day, added another double-bogey at the 12th hole before closing another bogey on a day when his latest bid for the career Grand Slam effectively came to an end.

McIlroy, who came into the year's third major fresh off a successful title defence in Canada, went out early and shot a three-under-par 67 and maintained a clean scorecard until a bogey at the final hole.

That left McIlroy level with Englishman Callum Tarren, Swede David Lingmerth, American Joel Dahmen and South Africa's MJ Daffue.

A month after an opening 65 in the US PGA, it was another welcome start to a major for McIlroy after previous struggles, but it was not without incident as he slammed one club into a bunker and threw another down the fairway on his final hole.

.@ahadwingolf's 4-under 66 on Thursday at The Country Club was his lowest career round in any major championship and earned him the @Lexus Top Performance of Day.#USOpen | #LexusGolf pic.twitter.com/VTr20DFxCS

After starting from the 10th, McIlroy had covered his first 13 holes in two under par before a pushed tee shot on the fifth finished in thick rough on the edge of a bunker and left him struggling to take a stance in the sand, with the ball well above his feet.