Shane Lowry stubbornly stuck to his guns and rallied late onin the first round of the Valero Texas Open in San Antonio. Competing in his final tournament before a debut in the US Masters, the Offalyman birdied two of his closing four holes for an opening 74, two-over, in difficult windy conditions.

The lone Irishman left in the field – after Graeme McDowell withdrew due to an ankle injury – Lowry was knocked back by a run of three successive bogeys from the seventh on his front nine and fell to four over on his round with another dropped shot on the 12th.

But Lowry fought back with birdies on the 14th, from 12 feet, and on the 347 yards Par 4 17th where he drove the green and two-putted from 18 feet to move into a share of 32nd position at the end of the first round when a persistently strong wind played havoc.

Charley Hoffman claimed the opening round lead with a superb 67, a shot clear of Australian Aaron Baddeley who had the distinction of holing out with his tee shot on the17th for a birdie: he had declared his original tee shot unplayable in a native area and walked back to the tee and holed out with what was his thirdstroke.

McDowell was forced to retire due to strained tendons in his left ankle, an injury sustained when practising earlier in the week. The Ulsterman had received treatment prior to his round and played with a heavilystrapped ankle until retiring.

He has added next week’s Shell Houston Open on to his schedule, ahead of playing in the Masters at Augusta.

“It was disappointing to withdraw, but the bigger picture Ihave to think about is the Masters. It’s a fatigue injury from practising thisweek and due to something new I had been trying in my game with regards to thefollow through,” explained McDowell.