As Seamus Power and Pádraig Harrington fired two over 74s, Shane Lowry broke par in his first competitive round for nine weeks with a rollercoaster, one-under 71 leaving him six shots behind Justin Rose after the opening round of the Farmers Insurance Open at Torrey Pines.

On a day when 14-time major winner Tiger Woods struggled badly off the tee and shot a four-over 76 in his first PGA Tour start for 17 months, the 29-year old Offaly man dug deep to break par on the theoretically easier North Course.

Lowry opened his 2017 account in ominous fashion with three consecutive bogeys. But he hit back with six birdies in the next eight holes before playing his last seven in two-over par.

The Clara talent found himself tied for ninth, just a stroke off the lead, after his mid-round fireworks. But he conjured a double bogey six at the 13th after driving into trouble and then three-putted the par-three 15th to undo all his good work and slither back to level par.

A birdie three at the 16th got him back into the red and represented his eighth single putt of a day that was remarkable for the fact that he hit just five fairways from the tee.

Driving accuracy is never a disadvantage at Torrey Pines, but waywardness is a big problem this week with both courses playing longer and tougher than normal with some wet weather leading to softer fairways and heavier rough.

Having taken seven putts to negotiate the first three holes — Lowry missed the first three greens and three-putted the second — he had just five putts more before the turn as he birdied the fourth, fifth, seventh, eighth and ninth with his birdie at the eighth requiring no putts at all.

In all, it was a reasonable start to the year for Lowry, who will be keen to make an early move in the FedEx Cup standings following his break.

In contrast, Power already has seven  2017 events under his belt and lies 84th in the standings,
But he came off second best on the North Course, mixing three birdies with three bogeys and a double bogey for a two over 74 that leaves him needing a sharp second round on the testing South Course on Friday to make his seventh cut from eight starts.

Starting the 10th, the West Waterford man birdied the 11th but then dropped four shots in a three-hole stretch by following bogeys at the 13th and 14th with a double-bogey five at the 15th, where he took four to get down from greenside sand.

Having turned in three over, he did well to come home in one under 35, finishing birdie-bogey-birdie to end the day provisionally tied for 112th.

Harrington has been battling a pinched nerve in his shoulder for several weeks and might have fared worse than his two over 74 on the South Course had he not been so sharp around the greens.

The 45-year old Dubliner hit just two of 14 fairways but scrambled successfully for par seven times out of 10, making up for additional bogeys at the 15th, 16th and first with an up-and-down from 158 yards for birdie at the 18th and another from 107 yards at the second.

Rose was sensational, carding two eagle threes, six birdies and three bogeys in a seven-under 65 on the "North" for a one-shot lead over Canada's Adam Hadwin, last week's runner-up and the latest member of "the 59 Club", who shot 66 on the "South".

As for the marquee three-ball — the world No. 1 Jason Day shot 73 and No. 2 Dustin Johnson a 72 — Woods was never comfortable with his swing and ended up hitting just four of 14 fairway and only nine of 18 greens in regulation figures.

The 40-year old Californian, who counts the 2008 US Open among his eight wins at Torrey Pines, opened with a bogey and added eight pars to turn in 37 in his first PGA Tour start for 17 months before struggling on the back nine.

Having birdied the 10th and 11th by holing a pair of 11 footers, he bogeyed the 12th, 13th and 14th before dropping two shots at the 15th.

Poor drives were his downfall each time and after another bogey at the 17th, he raised his arms in mock triumph on the 18th when he got up and down from 143 yards for birdie, holing an eight footer.

It was all a major contrast to the most recent of his major wins on the spectacular, clifftop La Jolla course nine years ago, when he won his third US Open.

On that occasion he outlasted Rocco Mediate in an 18-hole play-off for his 14th major win despite playing with a double stress fracture of his left tibia.