Starting on the back nine, Herbert struck four birdies and an eagle to turn in six-under before adding two more birdies on to overtake early pace-setters Matt Wallace and Eddie Pepperell on Thursday.

The English duo were a stroke behind the Australian in a tie for third place alongside Ireland's Shane Lowry, with China's Haotong Li in fifth on six under.

Garcia, named as a wildcard in the European Ryder Cup team, shared sixth place in a group of 10 players on five-under par.

The Spaniard missed the cut in all four majors this year but made an encouraging start in Vilamoura with birdies on the 10th, 12th and 14th holes to turn in three under.

RIGHT: Garcia opened with five-under 66 to share sixth place after the first round of the Portugal Masters. PHOTO: Warren Little/Getty Images.

He added four more birdies on the front nine and despite bogeys at the 3rd and 7th holes, Garcia was pleased not to show more signs of ring rust after taking a month-long break from golf.

"More than anything it's nice to be out here and … get the competitive juices going," said Garcia, whose last tournament appearance was at the Wyndham Championship in August.

"Obviously, I want to try to put together as many good rounds as possible but next week is different.

"The pressure is different, the atmosphere is different and I'm very excited for it.

"I would have loved it to be a little better. I played well, I didn't play extraordinarily. I still feel like I left easily three or four shots out there, a couple of easy birdie putts here and there."