RIYADH: Duncan Stewart never faced a serious challenge from anyone until a newly minted professional from the United States posed one, as he kept a one-stroke lead at 9-under in the American Express Dirab Golf Championship on Tuesday.

For a while, it looked like Stewart with a second round score of 3-under 69 on Tuesday and 135 total would take a 3-stroke lead into the final round of the tourment that is the fourth leg on the MENA Golf Tour under the aegis of the Golf in DUBAI.

Instead, Stewart has work cut out for him after Tommy Mou, a US-based Taiwanese who just turned pro after graduating from college at University of Florida two months ago, shot the round of the day, a 5-under 67, for an 8-under 136 total.

Stewart, from Scotland, and Mou who did varsity golf in the NCAA during his sophomore and senior years, will tee off in the last group at 11:30 a.m. with only one shot separating them in Wednesday’s final round, as they both try to win their first tournament on the MENA Tour.

Before Mou was done Stewart’s nearest challenger at three strokes back was Fredrik Quicker of Sweden who fired a 4-under 68 in Tuesday’s second round to sit on 138.

Two strokes further back on 140 were England’s Zane Scotland, who carded even par 72, and amateur Michael Harradine of Switzerland.

Englishman William Harrold is alone on 141 with four players namely Norway’s Andreas Friss, Tyler Hogarty of South Frica , Scotland’s Greg Nicolson and Nicholas Mullhaupt of Switzerland another stroke back on 142.

Saudi Arabia’s Faisal Salhab shot 73 on Tuesday for a 148 and was among the 10 leading amateurs that made the cut for the final round Wednesday.

Duncan tallied three birdies in what he called a “scrappy round.”

“I just didn’t have that many good shots like yesterday,” said Duncan who birdied No. 3 and the two par-5 holes on the back nine.

He hit three-wood from the tee to leave himself with a pitching wedge to the elevated green on the 417 yards third hole and sank the putt from 10 feet.

On 13, Duncan’s 3-iron hybrid second shot was 10 yards short of the green. He pitched to three feet of the cup and tapped in for birdie.

His superb chip shot from 67 yards that settled 6 inches from the hole set up his third birdie on 15.

Mou, 23, enjoyed a near-flawless short game that yielded 8 birdies against only three birdies.

“I hit it really close for easy putts although I had a couple of 12 footers,” said the lanky Mou.

“I’ll do the same. Not anything different and give myself good looks at birdie putts,” said Mou of Wednesday’s final round.

Mistakes on holes 3, 4 and 11 cost Mou strokes in an otherwise solid performance.